A speculative Revert for r165872 - Remove static thread pointers from CC, attempt 2

cc/scrollbar_animation_controller_linear_fade_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 "config.h"
 
 #include "cc/scrollbar_animation_controller_linear_fade.h"
 
 #include "cc/scrollbar_layer_impl.h"
 #include "cc/single_thread_proxy.h"
@@ skipping 12 matching lines @@
         m_contentLayer = m_scrollLayer->children()[0];
         m_scrollbarLayer = ScrollbarLayerImpl::create(3);
 
         m_scrollLayer->setMaxScrollPosition(IntSize(50, 50));
         m_contentLayer->setBounds(IntSize(50, 50));
 
         m_scrollbarController = ScrollbarAnimationControllerLinearFade::create(m_scrollLayer.get(), 2, 3);
         m_scrollbarController->setHorizontalScrollbarLayer(m_scrollbarLayer.get());
     }
 
+    DebugScopedSetImplThread implThread;
+
     scoped_ptr<ScrollbarAnimationControllerLinearFade> m_scrollbarController;
     scoped_ptr<LayerImpl> m_scrollLayer;
     LayerImpl* m_contentLayer;
     scoped_ptr<ScrollbarLayerImpl> m_scrollbarLayer;
 
 };
 
 TEST_F(ScrollbarAnimationControllerLinearFadeTest, verifyHiddenInBegin)
 {
     m_scrollbarController->animate(0);
@@ skipping 65 matching lines @@
     m_scrollbarController->animate(9);
     EXPECT_FLOAT_EQ(2 / 3.0f, m_scrollbarLayer->opacity());
     m_scrollbarController->animate(10);
     EXPECT_FLOAT_EQ(1 / 3.0f, m_scrollbarLayer->opacity());
     m_scrollbarController->animate(11);
     EXPECT_FLOAT_EQ(0, m_scrollbarLayer->opacity());
 
 }
 
 }