address feedback

Author: mmalerba

src/material/core/tokens/_token-utils.scss

@@ -78,3 +78,12 @@ $_component-prefix: null;
     @include mdc-theme.property($property, $value);
   }
 }
+
+// Merges together a list of maps into a single map.
+@function merge-all($maps...) {
+  $result: ();
+  @each $map in $maps {
+    $result: map.merge($result, $map);
+  }
+  @return $result;
+}

src/material/core/tokens/m2/mdc/_elevated-card.scss

@@ -69,14 +69,10 @@ $prefix: (mdc, elevated-card);
 // Combines the tokens generated by the above functions into a single map with placeholder values.
 // This is used to create token slots.
 @function get-token-slots() {
-  @return map.merge(
+  @return token-utils.merge-all(
           get-unthemable-tokens(),
-          map.merge(
-                  get-color-tokens(token-utils.$placeholder-color-config),
-                  map.merge(
-                          get-typography-tokens(token-utils.$placeholder-typography-config),
-                          get-density-tokens(token-utils.$placeholder-density-config)
-                  )
-          )
+          get-color-tokens(token-utils.$placeholder-color-config),
+          get-typography-tokens(token-utils.$placeholder-typography-config),
+          get-density-tokens(token-utils.$placeholder-density-config)
   );
 }

src/material/core/tokens/m2/mdc/_list.scss

@@ -207,14 +207,10 @@ $prefix: (mdc, list);
 // Combines the tokens generated by the above functions into a single map with placeholder values.
 // This is used to create token slots.
 @function get-token-slots() {
-  @return map.merge(
+  @return token-utils.merge-all(
           get-unthemable-tokens(),
-          map.merge(
-                  get-color-tokens(token-utils.$placeholder-color-config),
-                  map.merge(
-                          get-typography-tokens(token-utils.$placeholder-typography-config),
-                          get-density-tokens(token-utils.$placeholder-density-config)
-                  )
-          )
+          get-color-tokens(token-utils.$placeholder-color-config),
+          get-typography-tokens(token-utils.$placeholder-typography-config),
+          get-density-tokens(token-utils.$placeholder-density-config)
   );
 }

src/material/core/tokens/m2/mdc/_outlined-card.scss

@@ -78,14 +78,10 @@ $prefix: (mdc, outlined-card);
 // Combines the tokens generated by the above functions into a single map with placeholder values.
 // This is used to create token slots.
 @function get-token-slots() {
-  @return map.merge(
+  @return token-utils.merge-all(
           get-unthemable-tokens(),
-          map.merge(
-                  get-color-tokens(token-utils.$placeholder-color-config),
-                  map.merge(
-                          get-typography-tokens(token-utils.$placeholder-typography-config),
-                          get-density-tokens(token-utils.$placeholder-density-config)
-                  )
-          )
+          get-color-tokens(token-utils.$placeholder-color-config),
+          get-typography-tokens(token-utils.$placeholder-typography-config),
+          get-density-tokens(token-utils.$placeholder-density-config)
   );
 }