Pepper: Initialize PP_ImageDataDesc when creating ImageData.

Clears memory so we don't send unitialized memory to the
renderer.

BUG=391023

Review URL: https://codereview.chromium.org/383543004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@282222 0039d316-1c4b-4281-b951-d872f2087c98

ppapi/proxy/ppb_image_data_proxy.cc

@@ -494,7 +494,9 @@ PP_Resource PPB_ImageData_Proxy::CreateProxyResource(
   }
 
   HostResource result;
-  PP_ImageDataDesc desc;
+  // Initialize desc so we don't send unitialized memory over IPC.
+  // https://crbug.com/391023.
+  PP_ImageDataDesc desc = {};
   switch (type) {
     case PPB_ImageData_Shared::SIMPLE: {
       ppapi::proxy::SerializedHandle image_handle_wrapper;