Apps V2 in Pepper: introduce singleton resource ExtensionsCommon.

ppapi/proxy/ppb_instance_proxy.cc

Index: ppapi/proxy/ppb_instance_proxy.cc
diff --git a/ppapi/proxy/ppb_instance_proxy.cc b/ppapi/proxy/ppb_instance_proxy.cc
index 36d8b300ccf115d6f6cb971d3051ac9df9a75982..033cd30544e2ebe503cba21881c8b5edeafacf72 100644
--- a/ppapi/proxy/ppb_instance_proxy.cc
+++ b/ppapi/proxy/ppb_instance_proxy.cc
@@ -18,6 +18,7 @@
 #include "ppapi/proxy/browser_font_singleton_resource.h"
 #include "ppapi/proxy/content_decryptor_private_serializer.h"
 #include "ppapi/proxy/enter_proxy.h"
+#include "ppapi/proxy/extensions_common_resource.h"
 #include "ppapi/proxy/flash_clipboard_resource.h"
 #include "ppapi/proxy/flash_file_resource.h"
 #include "ppapi/proxy/flash_fullscreen_resource.h"
@@ -355,6 +356,9 @@ Resource* PPB_Instance_Proxy::GetSingletonResource(PP_Instance instance,
     case BROKER_SINGLETON_ID:
       new_singleton = new BrokerResource(connection, instance);
       break;
+    case EXTENSIONS_COMMON_SINGLETON_ID:
+      new_singleton = new ExtensionsCommonResource(connection, instance);
+      break;
     case GAMEPAD_SINGLETON_ID:
       new_singleton = new GamepadResource(connection, instance);
       break;