Moved the following IPC messages used by the chrome NPAPI plugin installer out of content

chrome/browser/chrome_plugin_message_filter.h

Index: chrome/browser/chrome_plugin_message_filter.h
===================================================================
--- chrome/browser/chrome_plugin_message_filter.h	(revision 98657)
+++ chrome/browser/chrome_plugin_message_filter.h	(working copy)
@@ -16,7 +16,7 @@
 class ChromePluginMessageFilter : public IPC::ChannelProxy::MessageFilter,
                                   public IPC::Message::Sender {
  public:
-  explicit ChromePluginMessageFilter(PluginProcessHost* process);
+  ChromePluginMessageFilter(PluginProcessHost* process);
 
   // BrowserMessageFilter methods:
   virtual bool OnMessageReceived(const IPC::Message& message);
@@ -35,7 +35,17 @@
                                         gfx::NativeWindow caller_window);
 #endif
   void OnGetPluginFinderUrl(std::string* plugin_finder_url);
+  void OnMissingPluginStatus(int status,
+                             int render_process_id,
+                             int render_view_id,
+                             gfx::NativeWindow window);
 
+  // static
+  static void HandleMissingPluginStatus(int status,
+                                        int render_process_id,
+                                        int render_view_id,
+                                        gfx::NativeWindow window);
+
   PluginProcessHost* process_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromePluginMessageFilter);