cc : Push layer lists instead of layer tree at commit and activation

cc/layers/scrollbar_layer_unittest.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 <stddef.h>
 
 #include <unordered_map>
 
 #include "base/threading/thread_task_runner_handle.h"
 #include "cc/animation/animation_host.h"
@@ skipping 127 matching lines @@
           scrollbar->Orientation(), thumb_thickness, track_start,
           kIsLeftSideVerticalScrollbar, child1->id());
     } else {
       child2 =
           PaintedScrollbarLayer::Create(std::move(scrollbar), child1->id());
     }
     layer_tree_root->AddChild(child1);
     layer_tree_root->InsertChild(child2, reverse_order ? 0 : 1);
     scrollbar_layer_id_ = reverse_order ? child1->id() : child2->id();
     host->SetRootLayer(layer_tree_root);
+    host->BuildPropertyTreesForTesting();
     return host->CommitAndCreateLayerImplTree();
   }
 
  protected:
   FakeLayerTreeHostClient fake_client_;
   TestTaskGraphRunner task_graph_runner_;
   LayerTreeSettings layer_tree_settings_;
   std::unique_ptr<FakeResourceTrackingLayerTreeHost> layer_tree_host_;
   int scrollbar_layer_id_;
 };
 
 TEST_F(ScrollbarLayerTest, ShouldScrollNonOverlayOnMainThread) {
   // Create and attach a non-overlay scrollbar.
   std::unique_ptr<Scrollbar> scrollbar(new FakeScrollbar);
   LayerImpl* layer_impl_tree_root = LayerImplForScrollAreaAndScrollbar(
       layer_tree_host_.get(), std::move(scrollbar), false, false, 0, 0);
   PaintedScrollbarLayerImpl* scrollbar_layer_impl =
       static_cast<PaintedScrollbarLayerImpl*>(
           layer_impl_tree_root->layer_tree_impl()->LayerById(
               scrollbar_layer_id_));
-  layer_impl_tree_root->layer_tree_impl()
-      ->BuildLayerListAndPropertyTreesForTesting();

[jaydasika, 2016/06/09 05:07:54]

Can't build property trees on compositor, they should be build on main thread
and send to it.

   ScrollTree& scroll_tree =
       layer_impl_tree_root->layer_tree_impl()->property_trees()->scroll_tree;
   ScrollNode* scroll_node =
       scroll_tree.Node(scrollbar_layer_impl->scroll_tree_index());
 
   // When the scrollbar is not an overlay scrollbar, the scroll should be
   // responded to on the main thread as the compositor does not yet implement
   // scrollbar scrolling.
   InputHandler::ScrollStatus status = layer_tree_host_->host_impl()->TryScroll(
       gfx::PointF(), InputHandler::TOUCHSCREEN, scroll_tree, scroll_node);
   EXPECT_EQ(InputHandler::SCROLL_ON_MAIN_THREAD, status.thread);
   EXPECT_EQ(MainThreadScrollingReason::kScrollbarScrolling,
             status.main_thread_scrolling_reasons);
 
   // Create and attach an overlay scrollbar.
   scrollbar.reset(new FakeScrollbar(false, false, true));
 
   layer_impl_tree_root = LayerImplForScrollAreaAndScrollbar(
       layer_tree_host_.get(), std::move(scrollbar), false, false, 0, 0);
   scrollbar_layer_impl = static_cast<PaintedScrollbarLayerImpl*>(
       layer_impl_tree_root->layer_tree_impl()->LayerById(scrollbar_layer_id_));
-  layer_impl_tree_root->layer_tree_impl()
-      ->BuildLayerListAndPropertyTreesForTesting();
   scroll_tree =
       layer_impl_tree_root->layer_tree_impl()->property_trees()->scroll_tree;
   scroll_node = scroll_tree.Node(scrollbar_layer_impl->scroll_tree_index());
 
   // The user shouldn't be able to drag an overlay scrollbar and the scroll
   // may be handled in the compositor.
   status = layer_tree_host_->host_impl()->TryScroll(
       gfx::PointF(), InputHandler::TOUCHSCREEN, scroll_tree, scroll_node);
   EXPECT_EQ(InputHandler::SCROLL_IGNORED, status.thread);
   EXPECT_EQ(MainThreadScrollingReason::kNotScrollable,
@@ skipping 946 matching lines @@
   TestScale(gfx::Rect(1240, 0, 15, 1333), 2.7754839f);
   TestScale(gfx::Rect(1240, 0, 15, 677), 2.46677136f);
 
   // Horizontal Scrollbars.
   TestScale(gfx::Rect(0, 1240, 1333, 15), 2.7754839f);
   TestScale(gfx::Rect(0, 1240, 677, 15), 2.46677136f);
 }
 
 }  // namespace
 }  // namespace cc