cc:: Use clip tree instead of layer tree during hit testing

cc/trees/layer_tree_impl_unittest.cc

 // 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 "cc/trees/layer_tree_impl.h"
 
 #include "cc/layers/heads_up_display_layer_impl.h"
 #include "cc/layers/layer.h"
 #include "cc/layers/solid_color_scrollbar_layer_impl.h"
 #include "cc/test/fake_impl_task_runner_provider.h"
@@ skipping 362 matching lines @@
   result_layer =
       host_impl().active_tree()->FindLayerThatIsHitByPoint(test_point);
   ASSERT_FALSE(result_layer);
 
   test_point = gfx::PointF(-1.f, 50.f);
   result_layer =
       host_impl().active_tree()->FindLayerThatIsHitByPoint(test_point);
   ASSERT_FALSE(result_layer);
 }
 
+TEST_F(LayerTreeImplTest, HitTestingSiblings) {
+  // This tests hit testing when the test point hits only one of the siblings.
+  gfx::Transform identity_matrix;
+  scoped_ptr<LayerImpl> root = LayerImpl::Create(host_impl().active_tree(), 1);
+  SetLayerPropertiesForTesting(root.get(), identity_matrix, gfx::Point3F(),
+                               gfx::PointF(), gfx::Size(100, 100), true, false,
+                               true);
+  scoped_ptr<LayerImpl> child1 =
+      LayerImpl::Create(host_impl().active_tree(), 2);
+  SetLayerPropertiesForTesting(child1.get(), identity_matrix, gfx::Point3F(),
+                               gfx::PointF(), gfx::Size(25, 25), true, false,
+                               false);
+  child1->SetMasksToBounds(true);
+  child1->SetDrawsContent(true);
+  scoped_ptr<LayerImpl> child2 =
+      LayerImpl::Create(host_impl().active_tree(), 3);
+  SetLayerPropertiesForTesting(child2.get(), identity_matrix, gfx::Point3F(),
+                               gfx::PointF(), gfx::Size(75, 75), true, false,
+                               false);
+  child2->SetMasksToBounds(true);
+  child2->SetDrawsContent(true);
+  root->AddChild(std::move(child1));
+  root->AddChild(std::move(child2));
+
+  host_impl().SetViewportSize(root->bounds());
+  host_impl().active_tree()->SetRootLayer(std::move(root));
+  host_impl().UpdateNumChildrenAndDrawPropertiesForActiveTree();
+
+  gfx::PointF test_point(50.f, 50.f);
+  LayerImpl* result_layer =
+      host_impl().active_tree()->FindLayerThatIsHitByPoint(test_point);
+  ASSERT_TRUE(result_layer);
+  EXPECT_EQ(3, result_layer->id());
+}
+
 TEST_F(LayerTreeImplTest, HitTestingForSinglePerspectiveLayer) {
   scoped_ptr<LayerImpl> root =
       LayerImpl::Create(host_impl().active_tree(), 12345);
 
   gfx::Transform identity_matrix;
 
   // perspective_projection_about_center * translation_by_z is designed so that
   // the 100 x 100 layer becomes 50 x 50, and remains centered at (50, 50).
   gfx::Transform perspective_projection_about_center;
   perspective_projection_about_center.Translate(50.0, 50.0);
@@ skipping 1844 matching lines @@
   EXPECT_EQ(0u, host_impl().active_tree()->NumLayers());
   scoped_ptr<LayerImpl> root = LayerImpl::Create(host_impl().active_tree(), 1);
   root->AddChild(LayerImpl::Create(host_impl().active_tree(), 2));
   root->AddChild(LayerImpl::Create(host_impl().active_tree(), 3));
   root->child_at(1)->AddChild(LayerImpl::Create(host_impl().active_tree(), 4));
   EXPECT_EQ(4u, host_impl().active_tree()->NumLayers());
 }
 
 }  // namespace
 }  // namespace cc