Iframe/div MD scrollbars get idle when mouse leaves the nested elements.

cc/trees/layer_tree_host_impl_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_impl.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <cmath>
@@ skipping 3212 matching lines @@
   EXPECT_TRUE(scrollbar_animation_controller->mouse_is_near_scrollbar());
 
   host_impl_->MouseMoveAt(gfx::Point(116, 100));
   EXPECT_FALSE(scrollbar_animation_controller->mouse_is_near_scrollbar());
 
   scrollbar_animation_controller->set_mouse_move_distance_for_test(102.f);
   host_impl_->MouseMoveAt(gfx::Point(116, 100));
   EXPECT_TRUE(scrollbar_animation_controller->mouse_is_near_scrollbar());
 
   did_request_redraw_ = false;
-  EXPECT_EQ(Layer::INVALID_ID,
-            host_impl_->scroll_layer_id_when_mouse_over_scrollbar());
+  EXPECT_FALSE(scrollbar_animation_controller->mouse_is_over_scrollbar());
   host_impl_->MouseMoveAt(gfx::Point(10, 100));
-  EXPECT_EQ(117, host_impl_->scroll_layer_id_when_mouse_over_scrollbar());
+  EXPECT_TRUE(scrollbar_animation_controller->mouse_is_over_scrollbar());
   host_impl_->MouseMoveAt(gfx::Point(10, 120));
-  EXPECT_EQ(117, host_impl_->scroll_layer_id_when_mouse_over_scrollbar());
+  EXPECT_TRUE(scrollbar_animation_controller->mouse_is_over_scrollbar());
   host_impl_->MouseMoveAt(gfx::Point(150, 120));
-  EXPECT_EQ(Layer::INVALID_ID,
-            host_impl_->scroll_layer_id_when_mouse_over_scrollbar());
+  EXPECT_FALSE(scrollbar_animation_controller->mouse_is_over_scrollbar());
 }
 
 TEST_F(LayerTreeHostImplTest, MouseMoveAtWithDeviceScaleOf1) {
   SetupMouseMoveAtWithDeviceScale(1.f);
 }
 
 TEST_F(LayerTreeHostImplTest, MouseMoveAtWithDeviceScaleOf2) {
   SetupMouseMoveAtWithDeviceScale(2.f);
 }
 
@@ skipping 8151 matching lines @@
   EXPECT_TRUE(host_impl_->use_gpu_rasterization());
 
   // Re-initialize with a software output surface.
   compositor_frame_sink_ = FakeCompositorFrameSink::CreateSoftware();
   host_impl_->InitializeRenderer(compositor_frame_sink_.get());
   EXPECT_FALSE(host_impl_->use_gpu_rasterization());
 }
 
 }  // namespace
 }  // namespace cc