fix(material/slider): handle null and undefined values in slider input

The slider values behaved inconsistently when we reset the formGroup. This MR will resolve that issue by setting `value` to default value when its `undefined` or `null`

Fixes #30614

Author: mistrykaran91

src/material/slider/slider-input.ts

@@ -96,7 +96,10 @@ export class MatSliderThumb implements _MatSliderThumb, OnDestroy, ControlValueA
     return numberAttribute(this._hostElement.value, 0);
   }
   set value(value: number) {
-    value = isNaN(value) ? 0 : value;
+    value = value && isNaN(value) ? 0 : value;
+    if (value === null || value === undefined) {
+      value = this._getDefaultValue();
+    }
     const stringValue = value + '';
     if (!this._hasSetInitialValue) {
       this._initialValue = stringValue;

src/material/slider/slider.ts

@@ -140,7 +140,7 @@ export class MatSlider implements AfterViewInit, OnDestroy, _MatSlider {
     return this._min;
   }
   set min(v: number) {
-    const min = isNaN(v) ? this._min : v;
+    const min = !v || isNaN(v) ? this._min : v;
     if (this._min !== min) {
       this._updateMin(min);
     }
@@ -216,7 +216,7 @@ export class MatSlider implements AfterViewInit, OnDestroy, _MatSlider {
     return this._max;
   }
   set max(v: number) {
-    const max = isNaN(v) ? this._max : v;
+    const max = !v || isNaN(v) ? this._max : v;
     if (this._max !== max) {
       this._updateMax(max);
     }