cc: Compute animation scale on demand

cc/trees/tree_synchronizer_unittest.cc

 // Copyright 2011 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/tree_synchronizer.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <set>
@@ skipping 639 matching lines @@
   scroll_offset_map.erase(transient_scroll_layer->id());
   scroll_offset_map[scroll_layer->id()]->SetCurrent(gfx::ScrollOffset(20, 30));
   scroll_offset_map[scroll_layer->id()]->PullDeltaForMainThread();
   scroll_offset_map[scroll_layer->id()]->SetCurrent(gfx::ScrollOffset(40, 50));
   scroll_offset_map[scroll_layer->id()]->PushFromMainThread(
       gfx::ScrollOffset(100, 100));
   scroll_offset_map[scroll_layer->id()]->PushPendingToActive();
   EXPECT_TRUE(is_equal(scroll_offset_map, scroll_tree.scroll_offset_map()));
 }
 
+TEST_F(TreeSynchronizerTest, RefreshPropertyTreesCachedData) {
+  host_->InitializeSingleThreaded(&client_, base::ThreadTaskRunnerHandle::Get(),
+                                  nullptr);
+  LayerTreeSettings settings;
+  FakeLayerTreeHostImplClient client;
+  FakeImplTaskRunnerProvider task_runner_provider;
+  FakeRenderingStatsInstrumentation stats_instrumentation;
+  TestSharedBitmapManager shared_bitmap_manager;
+  TestTaskGraphRunner task_graph_runner;
+  FakeLayerTreeHostImpl* host_impl = host_->host_impl();
+  host_impl->CreatePendingTree();
+
+  scoped_refptr<Layer> layer_tree_root = Layer::Create();
+  scoped_refptr<Layer> transform_layer = Layer::Create();
+
+  gfx::Transform scale_transform;
+  scale_transform.Scale3d(2.f, 2.f, 2.f);
+  // force adding a transform node for the layer
+  transform_layer->SetTransform(scale_transform);
+
+  layer_tree_root->AddChild(transform_layer);
+
+  host_->SetRootLayer(layer_tree_root);
+  host_->BuildPropertyTreesForTesting();
+  host_->CommitAndCreatePendingTree();
+  host_impl->ActivateSyncTree();
+
+  // arbitrarily set the animation scale for transform_layer and see if it is
+  // refreshed when pushing layer trees

[ajuma, 2016/06/30 21:57:37]

Style nit: Please write comments as sentences (capitalize the first letter, add
a period at the end). Same for the other comments you added.

+  host_impl->active_tree()->property_trees()->SetAnimationScalesForTesting(
+      transform_layer->transform_tree_index(), 10.f, 10.f);
+  EXPECT_EQ(
+      CombinedAnimationScale(10.f, 10.f),
+      host_impl->active_tree()->property_trees()->GetAnimationScales(
+          transform_layer->transform_tree_index(), host_impl->active_tree()));
+
+  host_impl->CreatePendingTree();
+  host_->CommitAndCreatePendingTree();
+  host_impl->ActivateSyncTree();
+  EXPECT_EQ(
+      CombinedAnimationScale(0.f, 0.f),
+      host_impl->active_tree()->property_trees()->GetAnimationScales(
+          transform_layer->transform_tree_index(), host_impl->active_tree()));
+}
+
 }  // namespace
 }  // namespace cc