Fix in process PPAPI decryption.

ppapi/proxy/ppp_content_decryptor_private_proxy.cc

Index: ppapi/proxy/ppp_content_decryptor_private_proxy.cc
diff --git a/ppapi/proxy/ppp_content_decryptor_private_proxy.cc b/ppapi/proxy/ppp_content_decryptor_private_proxy.cc
index 1b472074ed82c1f3bb3b485c34b14416e5d6a9f3..9aca5e7ee6557378b8a23112194c993b04d62d6d 100644
--- a/ppapi/proxy/ppp_content_decryptor_private_proxy.cc
+++ b/ppapi/proxy/ppp_content_decryptor_private_proxy.cc
@@ -75,22 +75,6 @@ PP_Var ExtractReceivedVarAndAddRef(Dispatcher* dispatcher,
   return var;
 }
 
-// Increments the reference count on |resource| to ensure that it remains valid
-// until the plugin receives the resource within the asynchronous message sent
-// from the proxy.  The plugin side takes ownership of that reference. Returns
-// PP_TRUE when the reference is successfully added, PP_FALSE otherwise.
-PP_Bool AddRefResourceForPlugin(HostDispatcher* dispatcher,
-                                PP_Resource resource) {
-  const PPB_Core* core = static_cast<const PPB_Core*>(
-      dispatcher->local_get_interface()(PPB_CORE_INTERFACE));
-  if (!core) {
-    NOTREACHED();
-    return PP_FALSE;
-  }
-  core->AddRefResource(resource);
-  return PP_TRUE;
-}

[dmichael (off chromium), 2012/12/13 19:20:35]

I was confused when reading the CL...  I think this AddRef still needs to
happen. What you're doing here is making sure that the Buffer Resource stays
valid long enough for the Plugin to take it. The messages you send (e.g., to
Decrypt) are asynchronous. If you don't AddRef them before sending them, I think
it's possible that the Buffer will be released before the plugin is done with
it.

I think you want to AddRef here (or maybe just before you send it, to make it
easier to balance?).

Maybe AddRefing right before you send, then RemoveRef on the plugin side right
after you call the related PPP function.

-
 bool InitializePppDecryptorBuffer(PP_Instance instance,
                                   HostDispatcher* dispatcher,
                                   PP_Resource resource,
@@ -107,9 +91,6 @@ bool InitializePppDecryptorBuffer(PP_Instance instance,
     return true;
   }
 
-  if (!AddRefResourceForPlugin(dispatcher, resource))
-    return false;
-
   HostResource host_resource;
   host_resource.SetHostResource(instance, resource);