Fixes issues when switching between software and compositing.

content/renderer/browser_plugin/browser_plugin_manager_impl.h

Index: content/renderer/browser_plugin/browser_plugin_manager_impl.h
diff --git a/content/renderer/browser_plugin/browser_plugin_manager_impl.h b/content/renderer/browser_plugin/browser_plugin_manager_impl.h
index eb69591ca29ef2c1546e9027f855f49f0c5e4a57..37f632406bb42286180ececdc65b4a1ad48713e1 100644
--- a/content/renderer/browser_plugin/browser_plugin_manager_impl.h
+++ b/content/renderer/browser_plugin/browser_plugin_manager_impl.h
@@ -7,6 +7,7 @@
 
 #include "content/renderer/browser_plugin/browser_plugin_manager.h"
 #include "googleurl/src/gurl.h"
+#include "ui/gfx/size.h"
 
 struct BrowserPluginMsg_UpdateRect_Params;
 class WebCursor;
@@ -38,6 +39,12 @@ class BrowserPluginManagerImpl : public BrowserPluginManager {
   void OnPluginAtPositionRequest(const IPC::Message& message,
                                  int request_id,
                                  const gfx::Point& position);
+  void OnUnhandledSwap(const IPC::Message& message,
+                       int instance_id,
+                       const gfx::Size& size,
+                       std::string mailbox_name,
+                       int gpu_route_id,
+                       int gpu_host_id);
 
   // Returns whether a message should be forwarded to BrowserPlugins.
   static bool ShouldForwardToBrowserPlugin(const IPC::Message& message);