feature(select): replace menu with native html select (#2462)

BREAKING CHANGE: The template and adapter APIs have changed to take advantage of the native select element; see the MDC Select README for more information.

demos/select.scss

@@ -15,9 +15,7 @@
 //
 
 @import "./common";
-@import "../packages/mdc-list/mdc-list";
-@import "../packages/mdc-menu/mdc-menu";
-@import "../packages/mdc-select/label/mixins";
+@import "../packages/mdc-button/mdc-button";
 @import "../packages/mdc-select/mdc-select";
 
 // stylelint-disable selector-class-pattern
@@ -34,4 +32,8 @@
 .demo-select-custom-colors.mdc-select--box {
   @include mdc-select-container-fill-color(rgba(blue, .1));
 }
+
+.button-container {
+  margin: 8px 0;
+}
 // stylelint-enable selector-class-pattern

packages/mdc-ripple/util.js

@@ -56,8 +56,9 @@ function detectEdgePseudoVarBug(windowObj) {
  */
 
 function supportsCssVariables(windowObj, forceRefresh = false) {
+  let supportsCssVariables = supportsCssVariables_;
   if (typeof supportsCssVariables_ === 'boolean' && !forceRefresh) {
-    return supportsCssVariables_;
+    return supportsCssVariables;
   }
 
   const supportsFunctionPresent = windowObj.CSS && typeof windowObj.CSS.supports === 'function';
@@ -74,11 +75,15 @@ function supportsCssVariables(windowObj, forceRefresh = false) {
   );
 
   if (explicitlySupportsCssVars || weAreFeatureDetectingSafari10plus) {
-    supportsCssVariables_ = !detectEdgePseudoVarBug(windowObj);
+    supportsCssVariables = !detectEdgePseudoVarBug(windowObj);
   } else {
-    supportsCssVariables_ = false;
+    supportsCssVariables = false;
   }
-  return supportsCssVariables_;
+
+  if (!forceRefresh) {
+    supportsCssVariables_ = supportsCssVariables;
+  }
+  return supportsCssVariables;
 }
 
 //