Remove unnecessary Platform::createMessagePortChannel method

content/ppapi_plugin/ppapi_webkitplatformsupport_impl.cc

Index: content/ppapi_plugin/ppapi_webkitplatformsupport_impl.cc
diff --git a/content/ppapi_plugin/ppapi_webkitplatformsupport_impl.cc b/content/ppapi_plugin/ppapi_webkitplatformsupport_impl.cc
index 948b02581ec01fcc10f11089111bd037bfdf3409..bdaf47d6869580f05e55eb712075f670063cf6bc 100644
--- a/content/ppapi_plugin/ppapi_webkitplatformsupport_impl.cc
+++ b/content/ppapi_plugin/ppapi_webkitplatformsupport_impl.cc
@@ -183,10 +183,12 @@ bool PpapiWebKitPlatformSupportImpl::isLinkVisited(
   return false;
 }
 
-blink::WebMessagePortChannel*
-PpapiWebKitPlatformSupportImpl::createMessagePortChannel() {
+void PpapiWebKitPlatformSupportImpl::createMessageChannel(
+    blink::WebMessagePortChannel** channel1,
+    blink::WebMessagePortChannel** channel2) {
   NOTREACHED();
-  return NULL;
+  *channel1 = NULL;
+  *channel2 = NULL;
 }
 
 void PpapiWebKitPlatformSupportImpl::setCookies(