Cache pending JS bridge sync IPC replies, and send in case of RenderFrame deletion.

content/common/android/gin_java_bridge_errors.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/common/android/gin_java_bridge_errors.h"
 
 #include "base/logging.h"
 
 namespace content {
 
 const char* GinJavaBridgeErrorToString(GinJavaBridgeError error) {
   switch (error) {
     case kGinJavaBridgeNoError:
       return "No error";
     case kGinJavaBridgeUnknownObjectId:
       return "Unknown Java object ID";
     case kGinJavaBridgeObjectIsGone:
       return "Java object is gone";
     case kGinJavaBridgeMethodNotFound:
       return "Method not found";
     case kGinJavaBridgeAccessToObjectGetClassIsBlocked:
       return "Access to java.lang.Object.getClass is blocked";
     case kGinJavaBridgeJavaExceptionRaised:
       return "Java exception was raised during method invocation";
     case kGinJavaBridgeNonAssignableTypes:
       return "The type of the object passed to the method is incompatible "
           "with the type of method's argument";
+    case kGinJavaBridgeRenderFrameDeleted:
+      return "RenderFrame has been deleted";
   }
   NOTREACHED();
   return "Unknown error";
 }
 
 }  // namespace content