[Mojo] Improve JavaScript API for MojoReadMessage

Originally, I tried to make the JavaScript bindings for the core Mojo APIs a
literal translation of the C APIs, but that makes MojoReadMessage a bit awkward
because C needs to worry much more about buffer allocation than JavaScript. In
building towards using the hello_world_service, I found that it was much easier
to push the MojoReadMessage pattern from connector.cc into C++ and make the
JavaScript API a bit more idiomatic by just returning an ArrayBuffer for the
message and an Array of handles.

BUG=317398

Review URL: https://codereview.chromium.org/83143002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@236999 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 8 insertions, 0 deletions

diff --git a/gin/converter.h b/gin/converter.h
index 33af452..2279319 100644
--- a/gin/converter.h
+++ b/gin/converter.h
@@ -88,6 +88,14 @@ struct Converter<v8::Handle<v8::Object> > {
 };
 
 template<>
+struct Converter<v8::Handle<v8::ArrayBuffer> > {
+  static v8::Handle<v8::Value> ToV8(v8::Isolate* isolate,
+                                    v8::Handle<v8::ArrayBuffer> val);
+  static bool FromV8(v8::Handle<v8::Value> val,
+                     v8::Handle<v8::ArrayBuffer>* out);
+};
+
+template<>
 struct Converter<v8::Handle<v8::External> > {
   static v8::Handle<v8::Value> ToV8(v8::Isolate* isolate,
                                     v8::Handle<v8::External> val);