Add new MouseCursor interface for setting the mouse cursor.

ppapi/proxy/ppb_instance_proxy.h

Index: ppapi/proxy/ppb_instance_proxy.h
diff --git a/ppapi/proxy/ppb_instance_proxy.h b/ppapi/proxy/ppb_instance_proxy.h
index 5b17af1492d5fb960d770512708cfe23f8e31ab3..a6efc5093a0cc452a88bd1cc7587a29c028555fc 100644
--- a/ppapi/proxy/ppb_instance_proxy.h
+++ b/ppapi/proxy/ppb_instance_proxy.h
@@ -100,6 +100,10 @@ class PPB_Instance_Proxy : public InterfaceProxy,
       PP_Instance instance,
       PP_URLComponents_Dev* components) OVERRIDE;
   virtual void PostMessage(PP_Instance instance, PP_Var message) OVERRIDE;
+  virtual PP_Bool SetCursor(PP_Instance instance,
+                            PP_MouseCursor_Type type,
+                            PP_Resource image,
+                            const PP_Point* hot_spot) OVERRIDE;
   virtual int32_t LockMouse(PP_Instance instance,
                             PP_CompletionCallback callback) OVERRIDE;
   virtual void UnlockMouse(PP_Instance instance) OVERRIDE;
@@ -162,6 +166,10 @@ class PPB_Instance_Proxy : public InterfaceProxy,
                                SerializedVarReturnValue result);
   void OnHostMsgGetPluginInstanceURL(PP_Instance instance,
                                      SerializedVarReturnValue result);
+  void OnHostMsgSetCursor(PP_Instance instance,
+                          int32_t type,
+                          const ppapi::HostResource& custom_image,
+                          const PP_Point& hot_spot);
 
   // Host -> Plugin message handlers.
   void OnPluginMsgMouseLockComplete(PP_Instance instance, int32_t result);