Step two of optionally sending messages to/from message ports as base::Value.

android_webview/native/aw_contents.cc

Index: android_webview/native/aw_contents.cc
diff --git a/android_webview/native/aw_contents.cc b/android_webview/native/aw_contents.cc
index 858047820c966a20833a69fe0c0db2e6879a8c5a..e192656d658e84743dd6e7be94758c48056b79c3 100644
--- a/android_webview/native/aw_contents.cc
+++ b/android_webview/native/aw_contents.cc
@@ -60,6 +60,7 @@
 #include "content/public/browser/render_process_host.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/web_contents.h"
+#include "content/public/common/message_port_types.h"
 #include "content/public/common/renderer_preferences.h"
 #include "content/public/common/ssl_status.h"
 #include "jni/AwContents_jni.h"
@@ -1113,11 +1114,14 @@ void AwContents::PostMessageToFrame(JNIEnv* env, jobject obj,
                    base::Unretained(AwMessagePortServiceImpl::GetInstance()),
                    j_ports));
   }
+  std::vector<content::TransferredMessagePort> ports(j_ports.size());
+  for (size_t i = 0; i < j_ports.size(); ++i)
+    ports[i].id = j_ports[i];
   content::MessagePortProvider::PostMessageToFrame(web_contents_.get(),
                                                    source_origin,
                                                    j_target_origin,
                                                    j_message,
-                                                   j_ports);
+                                                   ports);
 }
 
 scoped_refptr<AwMessagePortMessageFilter>