Use Date.now() for better browser compatibility

src/demo-app/ripple/ripple-demo.scss

@@ -1,3 +1,5 @@
+@import '../../lib/core/style/vendor-prefixes';
+
 .demo-ripple {
   button, a {
     margin: 8px;
@@ -15,10 +17,9 @@
     transition: all 200ms linear;
     width: 200px;
 
-    // Disable the blue overlay on touch and disable user text selection.
-    // This makes it easier to see ripples fading in.
+    // Disable the blue overlay on touch. This makes it easier to see ripples fading in.
     -webkit-tap-highlight-color: transparent;
-    user-select: none;
+    @include user-select(none);
 
     &.demo-ripple-disabled {
       color: rgba(32, 32, 32, 0.4);

src/lib/core/ripple/ripple-renderer.ts

@@ -21,7 +21,7 @@ export const RIPPLE_FADE_OUT_DURATION = 400;
  * Timeout for ignoring mouse events. Mouse events will be temporary ignored after touch
  * events to avoid synthetic mouse events.
  */
-const ignoreMouseEventsTimeout = 800;
+const IGNORE_MOUSE_EVENTS_TIMEOUT = 800;
 
 export type RippleConfig = {
   color?: string;
@@ -190,7 +190,7 @@ export class RippleRenderer {
   /** Function being called whenever the trigger is being pressed using mouse. */
   private onMousedown(event: MouseEvent) {
     const isSyntheticEvent = this._lastTouchStartEvent &&
-        event.timeStamp < this._lastTouchStartEvent + ignoreMouseEventsTimeout;
+        Date.now() < this._lastTouchStartEvent + IGNORE_MOUSE_EVENTS_TIMEOUT;
 
     if (!this.rippleDisabled && !isSyntheticEvent) {
       this._isPointerDown = true;
@@ -204,7 +204,7 @@ export class RippleRenderer {
       // Some browsers fire mouse events after a `touchstart` event. Those synthetic mouse
       // events will launch a second ripple if we don't ignore mouse events for a specific
       // time after a touchstart event.
-      this._lastTouchStartEvent = event.timeStamp;
+      this._lastTouchStartEvent = Date.now();
       this._isPointerDown = true;
 
       this.fadeInRipple(event.touches[0].clientX, event.touches[0].clientY, this.rippleConfig);