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

content/browser/android/java/gin_java_bridge_dispatcher_host.h

Index: content/browser/android/java/gin_java_bridge_dispatcher_host.h
diff --git a/content/browser/android/java/gin_java_bridge_dispatcher_host.h b/content/browser/android/java/gin_java_bridge_dispatcher_host.h
index 615c2b03770af4197ec1a0799a0cfe3bc4191b65..1fc89da36e1879aac821927305ac8f08dbce6c43 100644
--- a/content/browser/android/java/gin_java_bridge_dispatcher_host.h
+++ b/content/browser/android/java/gin_java_bridge_dispatcher_host.h
@@ -78,18 +78,14 @@ class GinJavaBridgeDispatcherHost
   bool IsValidRenderFrameHost(RenderFrameHost* render_frame_host);
   void SendReply(RenderFrameHost* render_frame_host, IPC::Message* reply_msg);
   void SendMethods(RenderFrameHost* render_frame_host,
-                   IPC::Message* reply_msg,
                    const std::set<std::string>& method_names);
   void SendHasMethodReply(RenderFrameHost* render_frame_host,
-                          IPC::Message* reply_msg,
                           bool result);
   void ProcessMethodInvocationResult(
       RenderFrameHost* render_frame_host,
-      IPC::Message* reply_msg,
       scoped_refptr<GinJavaMethodInvocationHelper> result);
   void ProcessMethodInvocationObjectResult(
       RenderFrameHost* render_frame_host,
-      IPC::Message* reply_msg,
       scoped_refptr<GinJavaMethodInvocationHelper> result);
   GinJavaBoundObject::ObjectID AddObject(
       const base::android::JavaRef<jobject>& object,
@@ -101,6 +97,7 @@ class GinJavaBridgeDispatcherHost
   void RemoveHolder(RenderFrameHost* holder,
                     const GinJavaBoundObject::ObjectMap::iterator& from,
                     size_t count);
+  IPC::Message* GetPendingReply(RenderFrameHost* render_frame_host);
 
   // Every time a GinJavaBoundObject backed by a real Java object is
   // created/destroyed, we insert/remove a strong ref to that Java object into
@@ -114,6 +111,13 @@ class GinJavaBridgeDispatcherHost
   typedef std::map<std::string, GinJavaBoundObject::ObjectID> NamedObjectMap;
   NamedObjectMap named_objects_;
 
+  // Keep track of pending calls out to Java such that we can send a synchronous
+  // reply to the renderer waiting on the response should the RenderFrame be
+  // destroyed while the reply is pending.
+  // Only used on the UI thread.
+  typedef std::map<RenderFrameHost*, IPC::Message*> PendingReplyMap;
+  PendingReplyMap pending_replies_;
+
   DISALLOW_COPY_AND_ASSIGN(GinJavaBridgeDispatcherHost);
 };