Takeover MT initiated animations from the compositor

third_party/WebKit/Source/platform/scroll/ScrollAnimatorCompositorCoordinator.cpp

 // 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.
 
 #include "platform/scroll/ScrollAnimatorCompositorCoordinator.h"
 
 #include "cc/animation/scroll_offset_animation_curve.h"
 #include "platform/RuntimeEnabledFeatures.h"
 #include "platform/animation/CompositorAnimationPlayer.h"
 #include "platform/animation/CompositorAnimationTimeline.h"
@@ skipping 42 matching lines @@
 bool ScrollAnimatorCompositorCoordinator::hasAnimationThatRequiresService() const
 {
     switch (m_runState) {
     case RunState::Idle:
     case RunState::RunningOnCompositor:
         return false;
     case RunState::PostAnimationCleanup:
     case RunState::WaitingToSendToCompositor:
     case RunState::RunningOnMainThread:
     case RunState::RunningOnCompositorButNeedsUpdate:
+    case RunState::RunningOnCompositorButNeedsTakeover:
     case RunState::WaitingToCancelOnCompositor:
         return true;
     }
     ASSERT_NOT_REACHED();
     return false;
 }
 
 bool ScrollAnimatorCompositorCoordinator::addAnimation(
     PassOwnPtr<CompositorAnimation> animation)
 {
@@ skipping 16 matching lines @@
         m_compositorPlayer->abortAnimation(m_compositorAnimationId);
 }
 
 void ScrollAnimatorCompositorCoordinator::cancelAnimation()
 {
     switch (m_runState) {
     case RunState::Idle:
     case RunState::WaitingToCancelOnCompositor:
     case RunState::PostAnimationCleanup:
         break;
+    case RunState::RunningOnCompositorButNeedsTakeover:
     case RunState::WaitingToSendToCompositor:
         if (m_compositorAnimationId) {
             // We still have a previous animation running on the compositor.
             m_runState = RunState::WaitingToCancelOnCompositor;
         } else {
             resetAnimationState();
         }
         break;
     case RunState::RunningOnMainThread:
         m_runState = RunState::PostAnimationCleanup;
         break;
     case RunState::RunningOnCompositorButNeedsUpdate:
     case RunState::RunningOnCompositor:
         m_runState = RunState::WaitingToCancelOnCompositor;
 
         // Get serviced the next time compositor updates are allowed.
         scrollableArea()->registerForAnimation();
     }
 }
 
+void ScrollAnimatorCompositorCoordinator::takeoverCompositorAnimation()
+{
+    switch (m_runState) {
+    case RunState::Idle:
+    case RunState::WaitingToCancelOnCompositor:
+    case RunState::PostAnimationCleanup:
+    case RunState::RunningOnCompositorButNeedsTakeover:
+    case RunState::WaitingToSendToCompositor:
+    case RunState::RunningOnMainThread:
+        break;
+    case RunState::RunningOnCompositorButNeedsUpdate:
+    case RunState::RunningOnCompositor:
+        // We call abortAnimation that makes changes to the animation running on
+        // the compositor. Thus, this function should only be called when in
+        // CompositingClean state.
+        abortAnimation();
+
+        m_runState = RunState::RunningOnCompositorButNeedsTakeover;
+
+        // Get serviced the next time compositor updates are allowed.
+        scrollableArea()->registerForAnimation();
+    }
+}
+
 void ScrollAnimatorCompositorCoordinator::compositorAnimationFinished(
     int groupId)
 {
     if (m_compositorAnimationGroupId != groupId)
         return;
 
     m_compositorAnimationId = 0;
     m_compositorAnimationGroupId = 0;
 
     switch (m_runState) {
     case RunState::Idle:
     case RunState::PostAnimationCleanup:
     case RunState::RunningOnMainThread:
         ASSERT_NOT_REACHED();
         break;
     case RunState::WaitingToSendToCompositor:
         break;
     case RunState::RunningOnCompositor:
     case RunState::RunningOnCompositorButNeedsUpdate:
+    case RunState::RunningOnCompositorButNeedsTakeover:
     case RunState::WaitingToCancelOnCompositor:
         m_runState = RunState::PostAnimationCleanup;
         // Get serviced the next time compositor updates are allowed.
         if (scrollableArea())
             scrollableArea()->registerForAnimation();
         else
             resetAnimationState();
     }
 }
 
@@ skipping 46 matching lines @@
     // animation.
     notifyCompositorAnimationFinished(group);
 }
 
 CompositorAnimationPlayer* ScrollAnimatorCompositorCoordinator::compositorPlayer() const
 {
     return m_compositorPlayer.get();
 }
 
 } // namespace blink