diff --git a/package.json b/package.json
index be1ab6ea7add..5b1e29d2e9ee 100644
--- a/package.json
+++ b/package.json
@@ -113,6 +113,7 @@
     "husky": "^1.3.1",
     "inquirer": "^6.2.0",
     "jasmine-core": "^3.5.0",
+    "kagekiri": "^1.0.18",
     "karma": "^4.4.1",
     "karma-browserstack-launcher": "^1.3.0",
     "karma-chrome-launcher": "^2.2.0",
diff --git a/rollup-globals.bzl b/rollup-globals.bzl
index 2f0ae3966c3b..32485f6154a3 100644
--- a/rollup-globals.bzl
+++ b/rollup-globals.bzl
@@ -69,6 +69,7 @@ ROLLUP_GLOBALS = {
     "@material/top-app-bar": "mdc.topAppBar",
 
     # Third-party libraries.
+    "kagekiri": "kagekiri",
     "moment": "moment",
     "protractor": "protractor",
     "rxjs": "rxjs",
diff --git a/src/cdk/testing/BUILD.bazel b/src/cdk/testing/BUILD.bazel
index 3967f007d85c..80855ba75c8c 100644
--- a/src/cdk/testing/BUILD.bazel
+++ b/src/cdk/testing/BUILD.bazel
@@ -26,7 +26,15 @@ filegroup(
 
 ng_web_test_suite(
     name = "unit_tests",
-    deps = ["//src/cdk/testing/tests:unit_test_sources"],
+    # We need to load Kagekiri statically since it is not a named AMD module and needs to
+    # be manually configured through "require.js" which is used by "karma_web_test_suite".
+    static_files = [
+        "@npm//kagekiri",
+    ],
+    deps = [
+        ":require-config.js",
+        "//src/cdk/testing/tests:unit_test_sources",
+    ],
 )
 
 e2e_test_suite(
diff --git a/src/cdk/testing/protractor/protractor-harness-environment.ts b/src/cdk/testing/protractor/protractor-harness-environment.ts
index 4ab26a73f1a2..1ff79296ddd8 100644
--- a/src/cdk/testing/protractor/protractor-harness-environment.ts
+++ b/src/cdk/testing/protractor/protractor-harness-environment.ts
@@ -7,18 +7,34 @@
  */
 
 import {HarnessEnvironment, HarnessLoader, TestElement} from '@angular/cdk/testing';
-import {by, element as protractorElement, ElementFinder} from 'protractor';
+import {by, element as protractorElement, ElementArrayFinder, ElementFinder} from 'protractor';
 import {ProtractorElement} from './protractor-element';
 
+/** Options to configure the environment. */
+export interface ProtractorHarnessEnvironmentOptions {
+  /** The query function used to find DOM elements. */
+  queryFn: (selector: string, root: ElementFinder) => ElementArrayFinder;
+}
+
+/** The default environment options. */
+const defaultEnvironmentOptions: ProtractorHarnessEnvironmentOptions = {
+  queryFn: (selector: string, root: ElementFinder) => root.all(by.css(selector))
+};
+
 /** A `HarnessEnvironment` implementation for Protractor. */
 export class ProtractorHarnessEnvironment extends HarnessEnvironment<ElementFinder> {
-  protected constructor(rawRootElement: ElementFinder) {
+  /** The options for this environment. */
+  private _options: ProtractorHarnessEnvironmentOptions;
+
+  protected constructor(
+      rawRootElement: ElementFinder, options?: ProtractorHarnessEnvironmentOptions) {
     super(rawRootElement);
+    this._options = {...defaultEnvironmentOptions, ...options};
   }
 
   /** Creates a `HarnessLoader` rooted at the document root. */
-  static loader(): HarnessLoader {
-    return new ProtractorHarnessEnvironment(protractorElement(by.css('body')));
+  static loader(options?: ProtractorHarnessEnvironmentOptions): HarnessLoader {
+    return new ProtractorHarnessEnvironment(protractorElement(by.css('body')), options);
   }
 
   async forceStabilize(): Promise<void> {}
@@ -37,15 +53,15 @@ export class ProtractorHarnessEnvironment extends HarnessEnvironment<ElementFind
   }
 
   protected createEnvironment(element: ElementFinder): HarnessEnvironment<ElementFinder> {
-    return new ProtractorHarnessEnvironment(element);
+    return new ProtractorHarnessEnvironment(element, this._options);
   }
 
   protected async getAllRawElements(selector: string): Promise<ElementFinder[]> {
-    const elementFinderArray = this.rawRootElement.all(by.css(selector));
-    const length = await elementFinderArray.count();
+    const elementArrayFinder = this._options.queryFn(selector, this.rawRootElement);
+    const length = await elementArrayFinder.count();
     const elements: ElementFinder[] = [];
     for (let i = 0; i < length; i++) {
-      elements.push(elementFinderArray.get(i));
+      elements.push(elementArrayFinder.get(i));
     }
     return elements;
   }
diff --git a/src/cdk/testing/require-config.js b/src/cdk/testing/require-config.js
new file mode 100644
index 000000000000..af84b376e6eb
--- /dev/null
+++ b/src/cdk/testing/require-config.js
@@ -0,0 +1,7 @@
+// Require.js is being used by the karma bazel rules and needs to be configured to properly
+// load AMD modules which are not explicitly named in their output bundle.
+require.config({
+  paths: {
+    'kagekiri': '/base/npm/node_modules/kagekiri/dist/kagekiri.umd.min',
+  }
+});
diff --git a/src/cdk/testing/testbed/testbed-harness-environment.ts b/src/cdk/testing/testbed/testbed-harness-environment.ts
index c5c3cb4d5aad..52d423601c69 100644
--- a/src/cdk/testing/testbed/testbed-harness-environment.ts
+++ b/src/cdk/testing/testbed/testbed-harness-environment.ts
@@ -19,31 +19,49 @@ import {takeWhile} from 'rxjs/operators';
 import {TaskState, TaskStateZoneInterceptor} from './task-state-zone-interceptor';
 import {UnitTestElement} from './unit-test-element';
 
+/** Options to configure the environment. */
+export interface TestbedHarnessEnvironmentOptions {
+  /** The query function used to find DOM elements. */
+  queryFn: (selector: string, root: Element) => Iterable<Element> | ArrayLike<Element>;
+}
+
+/** The default environment options. */
+const defaultEnvironmentOptions: TestbedHarnessEnvironmentOptions = {
+  queryFn: (selector: string, root: Element) => root.querySelectorAll(selector)
+};
 
 /** A `HarnessEnvironment` implementation for Angular's Testbed. */
 export class TestbedHarnessEnvironment extends HarnessEnvironment<Element> {
+  /** Whether the environment has been destroyed. */
   private _destroyed = false;
 
   /** Observable that emits whenever the test task state changes. */
   private _taskState: Observable<TaskState>;
 
-  protected constructor(rawRootElement: Element, private _fixture: ComponentFixture<unknown>) {
+  /** The options for this environment. */
+  private _options: TestbedHarnessEnvironmentOptions;
+
+  protected constructor(rawRootElement: Element, private _fixture: ComponentFixture<unknown>,
+      options?: TestbedHarnessEnvironmentOptions) {
     super(rawRootElement);
+    this._options = {...defaultEnvironmentOptions, ...options};
     this._taskState = TaskStateZoneInterceptor.setup();
     _fixture.componentRef.onDestroy(() => this._destroyed = true);
   }
 
   /** Creates a `HarnessLoader` rooted at the given fixture's root element. */
-  static loader(fixture: ComponentFixture<unknown>): HarnessLoader {
-    return new TestbedHarnessEnvironment(fixture.nativeElement, fixture);
+  static loader(fixture: ComponentFixture<unknown>, options?: TestbedHarnessEnvironmentOptions):
+      HarnessLoader {
+    return new TestbedHarnessEnvironment(fixture.nativeElement, fixture, options);
   }
 
   /**
    * Creates a `HarnessLoader` at the document root. This can be used if harnesses are
    * located outside of a fixture (e.g. overlays appended to the document body).
    */
-  static documentRootLoader(fixture: ComponentFixture<unknown>): HarnessLoader {
-    return new TestbedHarnessEnvironment(document.body, fixture);
+  static documentRootLoader(fixture: ComponentFixture<unknown>,
+      options?: TestbedHarnessEnvironmentOptions): HarnessLoader {
+    return new TestbedHarnessEnvironment(document.body, fixture, options);
   }
 
   /**
@@ -53,8 +71,9 @@ export class TestbedHarnessEnvironment extends HarnessEnvironment<Element> {
    * of the fixture.
    */
   static async harnessForFixture<T extends ComponentHarness>(
-      fixture: ComponentFixture<unknown>, harnessType: ComponentHarnessConstructor<T>): Promise<T> {
-    const environment = new TestbedHarnessEnvironment(fixture.nativeElement, fixture);
+      fixture: ComponentFixture<unknown>, harnessType: ComponentHarnessConstructor<T>,
+      options?: TestbedHarnessEnvironmentOptions): Promise<T> {
+    const environment = new TestbedHarnessEnvironment(fixture.nativeElement, fixture, options);
     await environment.forceStabilize();
     return environment.createComponentHarness(harnessType, fixture.nativeElement);
   }
@@ -95,11 +114,11 @@ export class TestbedHarnessEnvironment extends HarnessEnvironment<Element> {
   }
 
   protected createEnvironment(element: Element): HarnessEnvironment<Element> {
-    return new TestbedHarnessEnvironment(element, this._fixture);
+    return new TestbedHarnessEnvironment(element, this._fixture, this._options);
   }
 
   protected async getAllRawElements(selector: string): Promise<Element[]> {
     await this.forceStabilize();
-    return Array.from(this.rawRootElement.querySelectorAll(selector));
+    return Array.from(this._options.queryFn(selector, this.rawRootElement));
   }
 }
diff --git a/src/cdk/testing/tests/BUILD.bazel b/src/cdk/testing/tests/BUILD.bazel
index f1d088e7c86f..f845b0981c5c 100644
--- a/src/cdk/testing/tests/BUILD.bazel
+++ b/src/cdk/testing/tests/BUILD.bazel
@@ -9,12 +9,14 @@ ng_module(
         ["**/*.ts"],
         exclude = [
             "**/*.spec.ts",
+            "**/*.spec.d.ts",
             "harnesses/**",
         ],
     ),
     assets = glob(["**/*.html"]),
     deps = [
         "//src/cdk/keycodes",
+        "//src/cdk/platform",
         "@npm//@angular/forms",
     ],
 )
@@ -30,22 +32,30 @@ ts_library(
 ng_test_library(
     name = "unit_test_sources",
     srcs = glob(
-        ["**/*.spec.ts"],
+        [
+            "**/*.spec.ts",
+            "**/*.spec.d.ts",
+        ],
         exclude = ["**/*.e2e.spec.ts"],
     ),
     deps = [
         ":test_components",
         ":test_harnesses",
+        "//src/cdk/platform",
         "//src/cdk/testing",
         "//src/cdk/testing/private",
         "//src/cdk/testing/testbed",
         "@npm//@angular/platform-browser",
+        "@npm//kagekiri",
     ],
 )
 
 ng_e2e_test_library(
     name = "e2e_test_sources",
-    srcs = glob(["**/*.e2e.spec.ts"]),
+    srcs = glob([
+        "**/*.e2e.spec.ts",
+        "**/*.spec.d.ts",
+    ]),
     deps = [
         ":test_harnesses",
         "//src/cdk/testing",
diff --git a/src/cdk/testing/tests/harnesses/main-component-harness.ts b/src/cdk/testing/tests/harnesses/main-component-harness.ts
index 5ccf385b0c20..4694f8297b66 100644
--- a/src/cdk/testing/tests/harnesses/main-component-harness.ts
+++ b/src/cdk/testing/tests/harnesses/main-component-harness.ts
@@ -81,6 +81,9 @@ export class MainComponentHarness extends ComponentHarness {
       this.locatorForAll(SubComponentHarness, SubComponentSpecialHarness);
   readonly missingElementsAndHarnesses =
       this.locatorFor('.not-found', SubComponentHarness.with({title: /not found/}));
+  readonly shadows = this.locatorForAll('.in-the-shadows');
+  readonly deepShadow = this.locatorFor(
+      'test-shadow-boundary test-sub-shadow-boundary > .in-the-shadows');
 
   private _testTools = this.locatorFor(SubComponentHarness);
 
diff --git a/src/cdk/testing/tests/kagekiri.spec.d.ts b/src/cdk/testing/tests/kagekiri.spec.d.ts
new file mode 100644
index 000000000000..bfa43c5ae493
--- /dev/null
+++ b/src/cdk/testing/tests/kagekiri.spec.d.ts
@@ -0,0 +1,13 @@
+/**
+ * @license
+ * Copyright Google LLC All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
+// Note: kagekiri is a dev dependency that is used only in our tests to test using a custom
+// querySelector function. Do not use this in published code.
+declare module 'kagekiri' {
+  export function querySelectorAll(selector: string, root: Element): NodeListOf<Element>;
+}
diff --git a/src/cdk/testing/tests/protractor.e2e.spec.ts b/src/cdk/testing/tests/protractor.e2e.spec.ts
index 15bb9708f75f..bb8da1d692cd 100644
--- a/src/cdk/testing/tests/protractor.e2e.spec.ts
+++ b/src/cdk/testing/tests/protractor.e2e.spec.ts
@@ -5,10 +5,21 @@ import {
   TestElement
 } from '@angular/cdk/testing';
 import {ProtractorHarnessEnvironment} from '@angular/cdk/testing/protractor';
-import {browser} from 'protractor';
+import {browser, by, element as protractorElement, ElementFinder} from 'protractor';
 import {MainComponentHarness} from './harnesses/main-component-harness';
 import {SubComponentHarness, SubComponentSpecialHarness} from './harnesses/sub-component-harness';
 
+// Kagekiri is available globally in the browser. We declare it here so we can use it in the
+// browser-side script passed to `by.js`.
+// TODO(mmalerba): Replace with type-only import once TS 3.8 is available, see:
+//  https://devblogs.microsoft.com/typescript/announcing-typescript-3-8-beta/#type-only-imports-exports
+declare const kagekiri: {
+  querySelectorAll: (selector: string, root: Element) => NodeListOf<Element>;
+};
+
+const piercingQueryFn = (selector: string, root: ElementFinder) => protractorElement.all(by.js(
+    (s: string, r: Element) => kagekiri.querySelectorAll(s, r), selector, root.getWebElement()));
+
 describe('ProtractorHarnessEnvironment', () => {
   beforeEach(async () => {
     await browser.get('/component-harness');
@@ -460,6 +471,27 @@ describe('ProtractorHarnessEnvironment', () => {
       }
     });
   });
+
+    describe('shadow DOM interaction', () => {
+      it('should not pierce shadow boundary by default', async () => {
+        const harness = await ProtractorHarnessEnvironment.loader()
+            .getHarness(MainComponentHarness);
+        expect(await harness.shadows()).toEqual([]);
+      });
+
+      it('should pierce shadow boundary when using piercing query', async () => {
+        const harness = await ProtractorHarnessEnvironment.loader({queryFn: piercingQueryFn})
+            .getHarness(MainComponentHarness);
+        const shadows = await harness.shadows();
+        expect(await Promise.all(shadows.map(el => el.text()))).toEqual(['Shadow 1', 'Shadow 2']);
+      });
+
+      it('should allow querying across shadow boundary', async () => {
+        const harness = await ProtractorHarnessEnvironment.loader({queryFn: piercingQueryFn})
+            .getHarness(MainComponentHarness);
+        expect(await (await harness.deepShadow()).text()).toBe('Shadow 2');
+      });
+    });
 });
 
 async function checkIsElement(result: ComponentHarness | TestElement, selector?: string) {
diff --git a/src/cdk/testing/tests/test-components-module.ts b/src/cdk/testing/tests/test-components-module.ts
index 045c8633cbc7..10cef6eeaad7 100644
--- a/src/cdk/testing/tests/test-components-module.ts
+++ b/src/cdk/testing/tests/test-components-module.ts
@@ -10,11 +10,12 @@ import {CommonModule} from '@angular/common';
 import {NgModule} from '@angular/core';
 import {FormsModule} from '@angular/forms';
 import {TestMainComponent} from './test-main-component';
+import {TestShadowBoundary, TestSubShadowBoundary} from './test-shadow-boundary';
 import {TestSubComponent} from './test-sub-component';
 
 @NgModule({
   imports: [CommonModule, FormsModule],
-  declarations: [TestMainComponent, TestSubComponent],
-  exports: [TestMainComponent, TestSubComponent]
+  declarations: [TestMainComponent, TestSubComponent, TestShadowBoundary, TestSubShadowBoundary],
+  exports: [TestMainComponent, TestSubComponent, TestShadowBoundary, TestSubShadowBoundary]
 })
 export class TestComponentsModule {}
diff --git a/src/cdk/testing/tests/test-main-component.html b/src/cdk/testing/tests/test-main-component.html
index c57442de2a26..99998b6b0670 100644
--- a/src/cdk/testing/tests/test-main-component.html
+++ b/src/cdk/testing/tests/test-main-component.html
@@ -32,4 +32,4 @@ <h1 style="height: 100px; width: 200px;">Main Component</h1>
   </button>
   <span id="task-state-result" #taskStateResult></span>
 </div>
-
+<test-shadow-boundary *ngIf="_shadowDomSupported"></test-shadow-boundary>
diff --git a/src/cdk/testing/tests/test-main-component.ts b/src/cdk/testing/tests/test-main-component.ts
index 32c18182b0af..2c4d9fd551bb 100644
--- a/src/cdk/testing/tests/test-main-component.ts
+++ b/src/cdk/testing/tests/test-main-component.ts
@@ -7,6 +7,7 @@
  */
 
 import {ENTER} from '@angular/cdk/keycodes';
+import {_supportsShadowDom} from '@angular/cdk/platform';
 import {
   ChangeDetectionStrategy,
   ChangeDetectorRef,
@@ -42,6 +43,7 @@ export class TestMainComponent implements OnDestroy {
   specialKey = '';
   relativeX = 0;
   relativeY = 0;
+  _shadowDomSupported = _supportsShadowDom();
 
   @ViewChild('clickTestElement') clickTestElement: ElementRef<HTMLElement>;
   @ViewChild('taskStateResult') taskStateResultElement: ElementRef<HTMLElement>;
diff --git a/src/cdk/testing/tests/test-shadow-boundary.ts b/src/cdk/testing/tests/test-shadow-boundary.ts
new file mode 100644
index 000000000000..ee7cb1d0616d
--- /dev/null
+++ b/src/cdk/testing/tests/test-shadow-boundary.ts
@@ -0,0 +1,30 @@
+/**
+ * @license
+ * Copyright Google LLC All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
+import {ChangeDetectionStrategy, Component, ViewEncapsulation} from '@angular/core';
+
+@Component({
+  selector: 'test-shadow-boundary',
+  template: `
+    <div class="in-the-shadows">Shadow 1</div>
+    <test-sub-shadow-boundary></test-sub-shadow-boundary>
+  `,
+  changeDetection: ChangeDetectionStrategy.OnPush,
+  // tslint:disable-next-line:validate-decorators
+  encapsulation: ViewEncapsulation.ShadowDom,
+})
+export class TestShadowBoundary {}
+
+@Component({
+  selector: 'test-sub-shadow-boundary',
+  template: '<div class="in-the-shadows">Shadow 2</div>',
+  changeDetection: ChangeDetectionStrategy.OnPush,
+  // tslint:disable-next-line:validate-decorators
+  encapsulation: ViewEncapsulation.ShadowDom,
+})
+export class TestSubShadowBoundary {}
diff --git a/src/cdk/testing/tests/testbed.spec.ts b/src/cdk/testing/tests/testbed.spec.ts
index 8caa1b293212..59854ff67cbe 100644
--- a/src/cdk/testing/tests/testbed.spec.ts
+++ b/src/cdk/testing/tests/testbed.spec.ts
@@ -1,3 +1,4 @@
+import {_supportsShadowDom} from '@angular/cdk/platform';
 import {
   ComponentHarness,
   ComponentHarnessConstructor,
@@ -6,6 +7,7 @@ import {
 } from '@angular/cdk/testing';
 import {TestbedHarnessEnvironment} from '@angular/cdk/testing/testbed';
 import {async, ComponentFixture, fakeAsync, TestBed} from '@angular/core/testing';
+import {querySelectorAll as piercingQuerySelectorAll} from 'kagekiri';
 import {FakeOverlayHarness} from './harnesses/fake-overlay-harness';
 import {MainComponentHarness} from './harnesses/main-component-harness';
 import {SubComponentHarness, SubComponentSpecialHarness} from './harnesses/sub-component-harness';
@@ -504,6 +506,29 @@ describe('TestbedHarnessEnvironment', () => {
       }
     });
   });
+
+  if (_supportsShadowDom()) {
+    describe('shadow DOM interaction', () => {
+      it('should not pierce shadow boundary by default', async () => {
+        const harness = await TestbedHarnessEnvironment
+            .harnessForFixture(fixture, MainComponentHarness);
+        expect(await harness.shadows()).toEqual([]);
+      });
+
+      it('should pierce shadow boundary when using piercing query', async () => {
+        const harness = await TestbedHarnessEnvironment
+            .harnessForFixture(fixture, MainComponentHarness, {queryFn: piercingQuerySelectorAll});
+        const shadows = await harness.shadows();
+        expect(await Promise.all(shadows.map(el => el.text()))).toEqual(['Shadow 1', 'Shadow 2']);
+      });
+
+      it('should allow querying across shadow boundary', async () => {
+        const harness = await TestbedHarnessEnvironment
+            .harnessForFixture(fixture, MainComponentHarness, {queryFn: piercingQuerySelectorAll});
+        expect(await (await harness.deepShadow()).text()).toBe('Shadow 2');
+      });
+    });
+  }
 });
 
 async function checkIsElement(result: ComponentHarness | TestElement, selector?: string) {
diff --git a/src/e2e-app/BUILD.bazel b/src/e2e-app/BUILD.bazel
index 12e22b114f1d..184cd887aa64 100644
--- a/src/e2e-app/BUILD.bazel
+++ b/src/e2e-app/BUILD.bazel
@@ -102,6 +102,7 @@ ts_devserver(
     static_files = [
         "@npm//zone.js",
         "@npm//core-js",
+        "@npm//kagekiri",
         "@npm//material-components-web",
         "@npm//moment",
         "@npm//@webcomponents/custom-elements",
diff --git a/src/e2e-app/index.html b/src/e2e-app/index.html
index 79483f0eea7f..0c0c2844f426 100644
--- a/src/e2e-app/index.html
+++ b/src/e2e-app/index.html
@@ -29,6 +29,7 @@
   <!-- Static scripts which are not imported through AMD nor part of the ConcatJS bundle. -->
   <script src="core-js/client/core.min.js"></script>
   <script src="zone.js/dist/zone.min.js"></script>
+  <script src="kagekiri/dist/kagekiri.umd.min.js"></script>
 
   <!-- ConcatJS bundle from the Bazel TypeScript devserver. -->
   <script src="bundle.js"></script>
diff --git a/test/karma.conf.js b/test/karma.conf.js
index 3bdb13efd165..bc8006e55515 100644
--- a/test/karma.conf.js
+++ b/test/karma.conf.js
@@ -45,6 +45,7 @@ module.exports = config => {
         watched: false
       },
       {pattern: 'node_modules/@material/*/dist/*', included: false, watched: false},
+      {pattern: 'node_modules/kagekiri/**', included: false, watched: false},
 
       // Include all Angular dependencies
       {pattern: 'node_modules/@angular/**/*', included: false, watched: false},
diff --git a/tools/public_api_guard/cdk/testing/protractor.d.ts b/tools/public_api_guard/cdk/testing/protractor.d.ts
index a1e105b81cf0..0761944d3d74 100644
--- a/tools/public_api_guard/cdk/testing/protractor.d.ts
+++ b/tools/public_api_guard/cdk/testing/protractor.d.ts
@@ -19,12 +19,16 @@ export declare class ProtractorElement implements TestElement {
 }
 
 export declare class ProtractorHarnessEnvironment extends HarnessEnvironment<ElementFinder> {
-    protected constructor(rawRootElement: ElementFinder);
+    protected constructor(rawRootElement: ElementFinder, options?: ProtractorHarnessEnvironmentOptions);
     protected createEnvironment(element: ElementFinder): HarnessEnvironment<ElementFinder>;
     protected createTestElement(element: ElementFinder): TestElement;
     forceStabilize(): Promise<void>;
     protected getAllRawElements(selector: string): Promise<ElementFinder[]>;
     protected getDocumentRoot(): ElementFinder;
     waitForTasksOutsideAngular(): Promise<void>;
-    static loader(): HarnessLoader;
+    static loader(options?: ProtractorHarnessEnvironmentOptions): HarnessLoader;
+}
+
+export interface ProtractorHarnessEnvironmentOptions {
+    queryFn: (selector: string, root: ElementFinder) => ElementArrayFinder;
 }
diff --git a/tools/public_api_guard/cdk/testing/testbed.d.ts b/tools/public_api_guard/cdk/testing/testbed.d.ts
index d2572ad5cf17..a44594f0b0ef 100644
--- a/tools/public_api_guard/cdk/testing/testbed.d.ts
+++ b/tools/public_api_guard/cdk/testing/testbed.d.ts
@@ -1,14 +1,18 @@
 export declare class TestbedHarnessEnvironment extends HarnessEnvironment<Element> {
-    protected constructor(rawRootElement: Element, _fixture: ComponentFixture<unknown>);
+    protected constructor(rawRootElement: Element, _fixture: ComponentFixture<unknown>, options?: TestbedHarnessEnvironmentOptions);
     protected createEnvironment(element: Element): HarnessEnvironment<Element>;
     protected createTestElement(element: Element): TestElement;
     forceStabilize(): Promise<void>;
     protected getAllRawElements(selector: string): Promise<Element[]>;
     protected getDocumentRoot(): Element;
     waitForTasksOutsideAngular(): Promise<void>;
-    static documentRootLoader(fixture: ComponentFixture<unknown>): HarnessLoader;
-    static harnessForFixture<T extends ComponentHarness>(fixture: ComponentFixture<unknown>, harnessType: ComponentHarnessConstructor<T>): Promise<T>;
-    static loader(fixture: ComponentFixture<unknown>): HarnessLoader;
+    static documentRootLoader(fixture: ComponentFixture<unknown>, options?: TestbedHarnessEnvironmentOptions): HarnessLoader;
+    static harnessForFixture<T extends ComponentHarness>(fixture: ComponentFixture<unknown>, harnessType: ComponentHarnessConstructor<T>, options?: TestbedHarnessEnvironmentOptions): Promise<T>;
+    static loader(fixture: ComponentFixture<unknown>, options?: TestbedHarnessEnvironmentOptions): HarnessLoader;
+}
+
+export interface TestbedHarnessEnvironmentOptions {
+    queryFn: (selector: string, root: Element) => Iterable<Element> | ArrayLike<Element>;
 }
 
 export declare class UnitTestElement implements TestElement {
diff --git a/tools/system-config-tmpl.js b/tools/system-config-tmpl.js
index 33dbe96511f7..6e8cdae10997 100644
--- a/tools/system-config-tmpl.js
+++ b/tools/system-config-tmpl.js
@@ -31,6 +31,7 @@ var nodeModulesPath = '$NODE_MODULES_BASE_PATH';
 var pathMapping = {
   'tslib': 'node:tslib/tslib.js',
   'moment': 'node:moment/min/moment-with-locales.min.js',
+  'kagekiri': 'node:kagekiri/dist/kagekiri.umd.min.js',
 
   'rxjs': 'node:rxjs/bundles/rxjs.umd.min.js',
   'rxjs/operators': 'tools/system-rxjs-operators.js',
diff --git a/tslint.json b/tslint.json
index e085c84e39d7..dc603b940244 100644
--- a/tslint.json
+++ b/tslint.json
@@ -8,7 +8,8 @@
     "max-line-length": [true, {
         "limit": 100,
         "check-strings": true,
-        "check-regex": true
+        "check-regex": true,
+        "ignore-pattern": "//\\s+https?://"
       }
     ],
     // Disable this flag because of SHA tslint#48b0c597f9257712c7d1f04b55ed0aa60e333f6a
diff --git a/yarn.lock b/yarn.lock
index 7445ff9af27b..b644a9a29aba 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -6719,6 +6719,11 @@ jws@^3.0.0, jws@^3.1.4, jws@^3.1.5:
     jwa "^1.1.5"
     safe-buffer "^5.0.1"
 
+kagekiri@^1.0.18:
+  version "1.0.18"
+  resolved "https://registry.yarnpkg.com/kagekiri/-/kagekiri-1.0.18.tgz#4400714f37d79e7ec80c99aa5a0a59f729c1a6a7"
+  integrity sha512-J0dcWXcdzMDBOm3YE5sljkPfAHenv9zELJhjlfo/mxe98CtaaIXbC9JIjOfLk8m4B9hiATmkm5vBaBPrOOSbAQ==
+
 karma-browserstack-launcher@^1.3.0:
   version "1.3.0"
   resolved "https://registry.yarnpkg.com/karma-browserstack-launcher/-/karma-browserstack-launcher-1.3.0.tgz#61fe3d36b1cf10681e40f9d874bf37271fb1c674"