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

content/common/android/gin_java_bridge_errors.cc

Index: content/common/android/gin_java_bridge_errors.cc
diff --git a/content/common/android/gin_java_bridge_errors.cc b/content/common/android/gin_java_bridge_errors.cc
index 57326b38725c3ec864323453250f70300f379d14..b2458cd0354f50a93e4310414cde59621005c661 100644
--- a/content/common/android/gin_java_bridge_errors.cc
+++ b/content/common/android/gin_java_bridge_errors.cc
@@ -25,6 +25,8 @@ const char* GinJavaBridgeErrorToString(GinJavaBridgeError error) {
     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";