Introduce RenderWidgetHostViewWinTest for Tsf handling

ui/base/win/tsf_bridge.cc

 // Copyright (c) 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 <msctf.h>
 #include "base/logging.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/singleton.h"
 #include "base/message_loop.h"
@@ skipping 309 matching lines @@
     VLOG(1) << "Do not use TsfBridge without UI thread.";
     return false;
   }
   tls_tsf_bridge.Initialize(FreeTlsTsfBridgeDelegate);
   TsfBridgeDelegate* delegate = new TsfBridgeDelegate();
   tls_tsf_bridge.Set(delegate);
   return delegate->Initialize();
 }
 
 // static
+TsfBridge* TsfBridge::ReplaceForTesting(TsfBridge* bridge) {
+  if (MessageLoop::current()->type() != MessageLoop::TYPE_UI) {
+    VLOG(1) << "Do not use TsfBridge without UI thread.";
+    return NULL;
+  }
+  TsfBridge* old_bridge = TsfBridge::GetInstance();
+  tls_tsf_bridge.Set(bridge);
+  return old_bridge;
+}
+
+// static
 TsfBridge* TsfBridge::GetInstance() {
   if (MessageLoop::current()->type() != MessageLoop::TYPE_UI) {
     VLOG(1) << "Do not use TsfBridge without UI thread.";
     return NULL;
   }
   TsfBridgeDelegate* delegate =
       static_cast<TsfBridgeDelegate*>(tls_tsf_bridge.Get());
   DCHECK(delegate) << "Do no call GetInstance before TsfBridge::Initialize.";
   return delegate;
 }
 
 }  // namespace ui