Enable shadow DOM-based "missing plugin" placeholder.

chrome/renderer/plugins/shadow_dom_plugin_placeholder.h

Index: chrome/renderer/plugins/shadow_dom_plugin_placeholder.h
diff --git a/chrome/renderer/plugins/shadow_dom_plugin_placeholder.h b/chrome/renderer/plugins/shadow_dom_plugin_placeholder.h
new file mode 100644
index 0000000000000000000000000000000000000000..7a744fc09c3e3dab896cddc959cbc8f762fcc3f3
--- /dev/null
+++ b/chrome/renderer/plugins/shadow_dom_plugin_placeholder.h
@@ -0,0 +1,34 @@
+// Copyright 2014 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 CHROME_RENDERER_PLUGINS_SHADOW_DOM_PLUGIN_PLACEHOLDER_H_
+#define CHROME_RENDERER_PLUGINS_SHADOW_DOM_PLUGIN_PLACEHOLDER_H_
+
+#include "base/memory/scoped_ptr.h"
+#include "third_party/WebKit/public/web/WebPluginPlaceholder.h"
+
+struct ChromeViewHostMsg_GetPluginInfo_Output;
+
+namespace blink {
+struct WebPluginParams;
+}  // namespace blink
+
+// This is the Chrome implementation of shadow DOM plugin placeholders,
+// intended to ultimately replace those based on WebViewPlugin.
+// It is guarded by the --enable-plugin-placeholder-shadow-dom switch.
+
+// Returns |true| if shadow DOM plugin placeholders are enabled.
+bool ShadowDOMPluginPlaceholderEnabled();
+
+// Creates a placeholder given plugin info output.
+scoped_ptr<blink::WebPluginPlaceholder>
+CreateShadowDOMPlaceholderForPluginInfo(
+    const ChromeViewHostMsg_GetPluginInfo_Output& output,
+    const blink::WebPluginParams& orig_params);
+
+// Creates a placeholder suitable for representing a missing plugin.
+scoped_ptr<blink::WebPluginPlaceholder>
+CreateShadowDOMPlaceholderForMissingPlugin();
+
+#endif  // CHROME_RENDERER_PLUGINS_SHADOW_DOM_PLUGIN_PLACEHOLDER_H_