Optionally have MessagePort pass data as base::Value, part 1.

Various efforts (android webview, navigator.connect) are experimenting
with using MessagePort as a way to communicate with native code. This is
a start at refactoring MessagePort code to make this possible.

This CL changes the IPCs for MessagePort messages to pass the data as
a MessagePortMessage struct, adding support to the renderer side
MessagePort code to support both base::Value and blink::WebSerializedScriptValue
messages. Additionally a (currently unset) flag is added that determines
how MessagePort sends messages back to the browser process.

This is part of a series of changes:
[1/5] Blink side changes in https://codereview.chromium.org/924983002/ that expose a needed v8 context
[2/5] This CL
[3/5] https://codereview.chromium.org/944443003/ which causes the send_messages_as_values flag to be propagated
[4/5] https://codereview.chromium.org/938403005/ which uses this for navigator.connect services and adds infrastructure for layout tests
[5/5] https://codereview.chromium.org/940423004/ adds layout tests to blink to test these new features

BUG=426458

Review URL: https://codereview.chromium.org/921013002

Cr-Commit-Position: refs/heads/master@{#318492}

1 files changed, 4 insertions, 3 deletions

diff --git a/content/browser/message_port_service.h b/content/browser/message_port_service.h
index 5623e94..1e561b2 100644
--- a/content/browser/message_port_service.h
+++ b/content/browser/message_port_service.h
@@ -13,6 +13,7 @@
 #include "base/memory/singleton.h"
 #include "base/strings/string16.h"
 #include "content/common/content_export.h"
+#include "content/public/common/message_port_types.h"
 #include "ipc/ipc_message.h"
 
 namespace content {
@@ -20,7 +21,7 @@ class MessagePortDelegate;
 
 class CONTENT_EXPORT MessagePortService {
  public:
-  typedef std::vector<std::pair<base::string16, std::vector<int> > >
+  typedef std::vector<std::pair<content::MessagePortMessage, std::vector<int>>>
       QueuedMessages;
 
   // Returns the MessagePortService singleton.
@@ -33,7 +34,7 @@ class CONTENT_EXPORT MessagePortService {
   void Destroy(int message_port_id);
   void Entangle(int local_message_port_id, int remote_message_port_id);
   void PostMessage(int sender_message_port_id,
-                   const base::string16& message,
+                   const MessagePortMessage& message,
                    const std::vector<int>& sent_message_port_ids);
   void QueueMessages(int message_port_id);
   void SendQueuedMessages(int message_port_id,
@@ -72,7 +73,7 @@ class CONTENT_EXPORT MessagePortService {
   ~MessagePortService();
 
   void PostMessageTo(int message_port_id,
-                     const base::string16& message,
+                     const MessagePortMessage& message,
                      const std::vector<int>& sent_message_port_ids);
 
   // Handles the details of removing a message port id. Before calling this,