Compute if a layer is clipped outside CalcDrawProps

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_proxy.h"
@@ skipping 954 matching lines @@
     position = gfx::PointF();
     bounds = gfx::Size(200, 200);
     SetLayerPropertiesForTesting(scroll_child.get(), identity_matrix,
                                  transform_origin, position, bounds, true,
                                  false, false);
     scroll_child->SetDrawsContent(true);
 
     // This should cause scroll child and its descendants to be affected by
     // |child|'s clip.
     scroll_child->SetScrollParent(child.get());
+    scoped_ptr<std::set<LayerImpl*>> scroll_children(new std::set<LayerImpl*>);
+    scroll_children->insert(scroll_child.get());
+    child->SetScrollChildren(scroll_children.release());
 
     SetLayerPropertiesForTesting(grand_child.get(), identity_matrix,
                                  transform_origin, position, bounds, true,
                                  false, false);
     grand_child->SetDrawsContent(true);
     grand_child->SetHasRenderSurface(true);
 
     scroll_child->AddChild(grand_child.Pass());
     root->AddChild(scroll_child.Pass());
     root->AddChild(child.Pass());
@@ skipping 985 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