Use the WebTestProxy for layout tests in content_shell

content/public/test/content_layouttest_support.h

Index: content/public/test/content_layouttest_support.h
diff --git a/content/public/test/content_layouttest_support.h b/content/public/test/content_layouttest_support.h
new file mode 100644
index 0000000000000000000000000000000000000000..d2df68e7e3c42820061b8f5d2aa2f3ed31385713
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+++ b/content/public/test/content_layouttest_support.h
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+// Copyright (c) 2012 The Chromium Authors. All rights reserved.

[jam, 2012/11/08 20:37:06]

nit: get rid of "content_" in the filename, it's a bit redundant

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_PUBLIC_TEST_CONTENT_LAYOUTTEST_SUPPORT_H_
+#define CONTENT_PUBLIC_TEST_CONTENT_LAYOUTTEST_SUPPORT_H_
+
+#include "base/callback_forward.h"
+#include "content/common/content_export.h"
+
+namespace WebTestRunner {
+class WebTestProxyBase;
+}
+
+namespace content {
+
+// Enable injecting of a WebTestProxy between WebViews and RenderViews.
+// |callback| is invoked with a pointer to WebTestProxyBase for each created
+// WebTestProxy.
+CONTENT_EXPORT void EnableWebTestProxyCreation(
+    const base::Callback<void(WebTestRunner::WebTestProxyBase*)>& callback);
+
+}  // namespace content
+
+#endif  // CONTENT_PUBLIC_TEST_CONTENT_LAYOUTTEST_SUPPORT_H_