cc : Clean up cc clip tree

cc/trees/layer_tree_host_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/layer_tree_host.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 786 matching lines @@
     root_->AddChild(child_);
     layer_tree_host()->SetRootLayer(root_);
     LayerTreeHostTest::SetupTree();
   }
 
   void BeginTest() override { PostSetNeedsCommitToMainThread(); }
 
   void DidCommit() override {
     switch (layer_tree_host()->SourceFrameNumber()) {
       case 1:
-        // child_ should create transform, effect, clip node.
+        // child_ should create transform, effect node.
         child_->SetForceRenderSurfaceForTesting(true);
         break;
       case 2:
         // child_ should create a scroll node.
         child_->SetScrollClipLayerId(root_->id());
         break;
       case 3:
+        // child_ should create a clip node.
+        child_->SetMasksToBounds(true);
+        break;
+      case 4:
         // child_ should not create any property tree node.
+        child_->SetMasksToBounds(false);
         child_->SetForceRenderSurfaceForTesting(false);
         child_->SetScrollClipLayerId(Layer::INVALID_ID);
     }
   }
 
   void CommitCompleteOnThread(LayerTreeHostImpl* impl) override {
     PropertyTrees* property_trees = impl->sync_tree()->property_trees();
     const TransformNode* root_transform_node =
         property_trees->transform_tree.FindNodeFromOwningLayerId(root_->id());
     const TransformNode* child_transform_node =
         property_trees->transform_tree.FindNodeFromOwningLayerId(child_->id());
     const EffectNode* root_effect_node =
         property_trees->effect_tree.FindNodeFromOwningLayerId(root_->id());
     const EffectNode* child_effect_node =
         property_trees->effect_tree.FindNodeFromOwningLayerId(child_->id());
     const ClipNode* root_clip_node =
         property_trees->clip_tree.FindNodeFromOwningLayerId(root_->id());
     const ClipNode* child_clip_node =
         property_trees->clip_tree.FindNodeFromOwningLayerId(child_->id());
     const ScrollNode* root_scroll_node =
         property_trees->scroll_tree.FindNodeFromOwningLayerId(root_->id());
     const ScrollNode* child_scroll_node =
         property_trees->scroll_tree.FindNodeFromOwningLayerId(child_->id());
     switch (impl->sync_tree()->source_frame_number()) {
       case 0:
-        // root_ should create every property tree node and child_ should not
-        // create any.
+        // root_ should create transform, scroll and effect tree nodes but not
+        // a clip node.
         EXPECT_NE(root_transform_node, nullptr);
         EXPECT_EQ(root_transform_node->id, root_->transform_tree_index());
         EXPECT_NE(root_effect_node, nullptr);
         EXPECT_EQ(root_effect_node->id, root_->effect_tree_index());
-        EXPECT_NE(root_clip_node, nullptr);
-        EXPECT_EQ(root_clip_node->id, root_->clip_tree_index());
         EXPECT_NE(root_scroll_node, nullptr);
         EXPECT_EQ(root_scroll_node->id, root_->scroll_tree_index());
+        EXPECT_EQ(root_clip_node, nullptr);
         EXPECT_EQ(child_transform_node, nullptr);
         EXPECT_EQ(child_effect_node, nullptr);
         EXPECT_EQ(child_clip_node, nullptr);
         EXPECT_EQ(child_scroll_node, nullptr);
         break;
       case 1:
-        // child_ should create a transfrom, clip, effect nodes but not a scroll
+        // child_ should create a transfrom, effect nodes but not a scroll, clip
         // node.
         EXPECT_NE(child_transform_node, nullptr);
         EXPECT_EQ(child_transform_node->id, child_->transform_tree_index());
         EXPECT_NE(child_effect_node, nullptr);
         EXPECT_EQ(child_effect_node->id, child_->effect_tree_index());
-        EXPECT_NE(child_clip_node, nullptr);
-        EXPECT_EQ(child_clip_node->id, child_->clip_tree_index());
+        EXPECT_EQ(child_clip_node, nullptr);
         EXPECT_EQ(child_scroll_node, nullptr);
         break;
       case 2:
         // child_ should create a scroll node.
         EXPECT_NE(child_scroll_node, nullptr);
         EXPECT_EQ(child_scroll_node->id, child_->scroll_tree_index());
         break;
       case 3:
+        // child_ should create a clip node.
+        EXPECT_NE(child_clip_node, nullptr);
+        EXPECT_EQ(child_clip_node->id, child_->clip_tree_index());
+        break;
+      case 4:
         // child_ should not create any property tree nodes.
         EXPECT_EQ(child_transform_node, nullptr);
         EXPECT_EQ(child_effect_node, nullptr);
         EXPECT_EQ(child_clip_node, nullptr);
         EXPECT_EQ(child_scroll_node, nullptr);
         EndTest();
         break;
     }
   }
 
@@ skipping 6302 matching lines @@
 
  private:
   bool first_ = true;
   SkBitmap bitmap_;
 };
 
 SINGLE_AND_MULTI_THREAD_TEST_F(LayerTreeHostTestQueueImageDecodeNonLazy);
 
 }  // namespace
 }  // namespace cc