Animations: Port LinkHighlight to use compositor timelines.

Source/web/WebViewImpl.h

Index: Source/web/WebViewImpl.h
diff --git a/Source/web/WebViewImpl.h b/Source/web/WebViewImpl.h
index 7f2884d206cf10b70be832f3dc6be9b81081aa43..95fc4baac45e37e6de53e51609e565f665271e91 100644
--- a/Source/web/WebViewImpl.h
+++ b/Source/web/WebViewImpl.h
@@ -37,6 +37,7 @@
 #include "platform/geometry/IntRect.h"
 #include "platform/graphics/GraphicsLayer.h"
 #include "platform/heap/Handle.h"
+#include "public/platform/WebCompositorAnimationTimeline.h"
 #include "public/platform/WebDisplayMode.h"
 #include "public/platform/WebFloatSize.h"
 #include "public/platform/WebGestureCurveTarget.h"
@@ -77,7 +78,6 @@ class DeprecatedPaintLayerCompositor;
 class TopControls;
 class UserGestureToken;
 class WebActiveGestureAnimation;
-class WebCompositorAnimationTimeline;
 class WebDevToolsAgentImpl;
 class WebElement;
 class WebLayerTreeView;
@@ -441,6 +441,7 @@ public:
     void scheduleAnimation();
     void attachCompositorAnimationTimeline(WebCompositorAnimationTimeline*);
     void detachCompositorAnimationTimeline(WebCompositorAnimationTimeline*);
+    WebCompositorAnimationTimeline* linkHighlightsTimeline() const { return m_linkHighlightsTimeline.get(); }
 
     void setVisibilityState(WebPageVisibilityState, bool) override;
 
@@ -739,6 +740,7 @@ private:
     int m_flingModifier;
     bool m_flingSourceDevice;
     Vector<OwnPtr<LinkHighlight>> m_linkHighlights;
+    OwnPtr<WebCompositorAnimationTimeline> m_linkHighlightsTimeline;
     OwnPtrWillBePersistent<FullscreenController> m_fullscreenController;
 
     bool m_showFPSCounter;