Share animations from compositor to main thread.

third_party/WebKit/public/platform/WebCompositorAnimationDelegate.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef WebCompositorAnimationDelegate_h
 #define WebCompositorAnimationDelegate_h
 
 #include "WebCommon.h"
+#include "cc/animation/animation_curve.h"
 
 namespace blink {
 
 class BLINK_PLATFORM_EXPORT WebCompositorAnimationDelegate {
 public:
     virtual ~WebCompositorAnimationDelegate() { }
 
     virtual void notifyAnimationStarted(double monotonicTime, int group) = 0;
     virtual void notifyAnimationFinished(double monotonicTime, int group) = 0;
     virtual void notifyAnimationAborted(double monotonicTime, int group) = 0;
+    // TODO(ymalik): Make pure virtual.

[ymalik, 2016/02/26 19:05:25]

I tried to make this pure virtual, but had the following problem:
Source/core/animation/Animation.h inherits this class. When I override the
function there, I get an error when I try to upload that we shouldn't reference
cc in Source/core. Thats strange because WebCompositorAnimationDelegate is in
public/platform and can reference cc, and Animation includes
WebCompositorAnimationDelegate, so it should also be allowed to reference cc?

[ajuma, 2016/02/26 23:56:54]

No, core isn't allowed to refer to cc types. The options seem to be to leave
this as non-pure virtual or to define a subclass (say in platform/graphics) that
provides an override and then subclass *that* in core instead of subclassing
WebCompositorAnimationDelegate. I'll leave this up to whoever does the public/
OWNERS review for this CL.

[ymalik, 2016/02/29 16:31:09]

Acknowledged.

[Rick Byers, 2016/02/29 20:21:35]

I think a regular virtual is probably OK if you can describe (in a comment here)
why it's OK for only the classes with access to 'cc' to be able to implement
this method.  In particular, since blink's Animation class is handling
notifyAnimationStarted, won't it also really want to know about
animationTakeover cases?

+    virtual void notifyAnimationTakeover(
+        double monotonicTime,
+        double animationStartTime,
+        scoped_ptr<cc::AnimationCurve> curve) { }
 };
 
 } // namespace blink
 
 #endif // WebCompositorAnimationDelegate_h