Reland: Plugin Placeholders: Refactor for platforms that don't support plugins

content/shell/renderer/layout_test/test_plugin_placeholder.h

Index: content/shell/renderer/layout_test/test_plugin_placeholder.h
diff --git a/content/shell/renderer/layout_test/test_plugin_placeholder.h b/content/shell/renderer/layout_test/test_plugin_placeholder.h
deleted file mode 100644
index 1424923f31d36fac94bf13cc1c609401c32e8647..0000000000000000000000000000000000000000
--- a/content/shell/renderer/layout_test/test_plugin_placeholder.h
+++ /dev/null
@@ -1,23 +0,0 @@
-// Copyright 2015 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.
-#ifndef CONTENT_SHELL_RENDERER_TEST_RUNNER_TEST_PLUGIN_PLACEHOLDER_H_
-#define CONTENT_SHELL_RENDERER_TEST_RUNNER_TEST_PLUGIN_PLACEHOLDER_H_
-
-#include "components/plugins/renderer/plugin_placeholder.h"
-
-namespace content {
-
-// A subclass of PluginPlaceholder for use in Blink layout tests.
-class TestPluginPlaceholder : public plugins::PluginPlaceholder {
- public:
-  TestPluginPlaceholder(RenderFrame* render_frame,
-                        blink::WebLocalFrame* frame,
-                        const blink::WebPluginParams& params);
-
-  void BindWebFrame(blink::WebFrame* frame) override;
-};
-
-}  // namespace content
-
-#endif  // CONTENT_SHELL_RENDERER_TEST_RUNNER_TEST_PLUGIN_PLACEHOLDER_H_