cc: Clean up LayerTreeTest and TestHooks.

cc/test/layer_tree_test.h

Index: cc/test/layer_tree_test.h
diff --git a/cc/test/layer_tree_test.h b/cc/test/layer_tree_test.h
index 140cc7927bf9135796c0aa718f94d5d31738546f..714c046b4c41b89a85b6cc398b343a9491d10900 100644
--- a/cc/test/layer_tree_test.h
+++ b/cc/test/layer_tree_test.h
@@ -8,8 +8,6 @@
 #include "base/memory/ref_counted.h"
 #include "base/threading/thread.h"
 #include "cc/animation/animation_delegate.h"
-#include "cc/test/proxy_impl_for_test.h"
-#include "cc/test/proxy_main_for_test.h"
 #include "cc/test/remote_proto_channel_bridge.h"
 #include "cc/test/test_hooks.h"
 #include "cc/trees/layer_tree_host.h"
@@ -26,12 +24,13 @@ class LayerTreeHost;
 class LayerTreeHostForTesting;
 class LayerTreeHostClient;
 class LayerTreeHostImpl;
+class ProxyImpl;
+class ProxyMain;
 class RemoteChannelImplForTest;
 class TestContextProvider;
 class TestGpuMemoryBufferManager;
 class TestTaskGraphRunner;
 class TestWebGraphicsContext3D;
-class ThreadedChannelForTest;
 
 // Creates the virtual viewport layer hierarchy under the given root_layer.
 // Convenient overload of the method below that creates a scrolling layer as
@@ -128,11 +127,7 @@ class LayerTreeTest : public testing::Test, public TestHooks {
 
   bool HasImplThread() const { return !!impl_thread_; }
   base::SingleThreadTaskRunner* ImplThreadTaskRunner() {
-    DCHECK(task_runner_provider());
-    base::SingleThreadTaskRunner* impl_thread_task_runner =
-        task_runner_provider()->ImplThreadTaskRunner();
-    return impl_thread_task_runner ? impl_thread_task_runner
-                                   : main_task_runner_.get();
+    return impl_task_runner_.get();
   }
   base::SingleThreadTaskRunner* MainThreadTaskRunner() {
     return main_task_runner_.get();
@@ -155,16 +150,6 @@ class LayerTreeTest : public testing::Test, public TestHooks {
     return gpu_memory_buffer_manager_.get();
   }
 
-  // Use these only for tests in threaded or remote mode.
-  ProxyMainForTest* GetProxyMainForTest() const;
-  ProxyImplForTest* GetProxyImplForTest() const;
-
-  // Use this only for tests in threaded mode.
-  ThreadedChannelForTest* GetThreadedChannelForTest() const;
-
-  // Use this only for tests in remote mode.
-  RemoteChannelImplForTest* GetRemoteChannelImplForTest() const;
-
   void DestroyLayerTreeHost();
   void DestroyRemoteClientHost() override;
 
@@ -208,6 +193,7 @@ class LayerTreeTest : public testing::Test, public TestHooks {
   int timeout_seconds_;
 
   scoped_refptr<base::SingleThreadTaskRunner> main_task_runner_;
+  scoped_refptr<base::SingleThreadTaskRunner> impl_task_runner_;
   std::unique_ptr<base::Thread> impl_thread_;
   std::unique_ptr<SharedBitmapManager> shared_bitmap_manager_;
   std::unique_ptr<TestGpuMemoryBufferManager> gpu_memory_buffer_manager_;