cc: Avoid updating animations in the background without an active tree

cc/trees/layer_tree_host_unittest_animation.cc

 // Copyright 2012 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 "cc/trees/layer_tree_host.h"
 
 #include "cc/animation/animation_curve.h"
 #include "cc/animation/layer_animation_controller.h"
 #include "cc/animation/timing_function.h"
 #include "cc/layers/layer.h"
@@ skipping 86 matching lines @@
     }
     EndTest();
   }
 
   virtual void AfterTest() OVERRIDE {}
 
  private:
   int num_animates_;
 };
 
-// Temporarily suppressed per crbug.com/280706.
-//MULTI_THREAD_TEST_F(
-//    LayerTreeHostAnimationTestSetNeedsAnimateInsideAnimationCallback);
+MULTI_THREAD_TEST_F(
+    LayerTreeHostAnimationTestSetNeedsAnimateInsideAnimationCallback);
 
 // Add a layer animation and confirm that
 // LayerTreeHostImpl::updateAnimationState does get called and continues to
 // get called.
 class LayerTreeHostAnimationTestAddAnimation
     : public LayerTreeHostAnimationTest {
  public:
   LayerTreeHostAnimationTestAddAnimation()
       : num_animates_(0),
         received_animation_started_notification_(false),
@@ skipping 678 matching lines @@
   int finished_times_;
   FakeContentLayerClient client_;
   scoped_refptr<FakeContentLayer> content_;
 };
 
 MULTI_THREAD_TEST_F(
     LayerTreeHostAnimationTestCheckerboardDoesntStartAnimations);
 
 }  // namespace
 }  // namespace cc