Update mojom parser to allow array of arrays.

mojo/bindings/js/codec_unittests.js

Index: mojo/bindings/js/codec_unittests.js
diff --git a/mojo/bindings/js/codec_unittests.js b/mojo/bindings/js/codec_unittests.js
index a5040544e4088f751dd8f6ce9982a4fe800a00e8..27cfb5c97b616b7626ad4a9cf54a20c63bb72b79 100644
--- a/mojo/bindings/js/codec_unittests.js
+++ b/mojo/bindings/js/codec_unittests.js
@@ -84,7 +84,7 @@ define([
     foo.source = 23423782;
 
     var messageName = 31;
-    var payloadSize = 224;
+    var payloadSize = 240;
 
     var builder = new codec.MessageBuilder(messageName, payloadSize);
     builder.encodeStruct(sample.Foo, foo);
@@ -94,10 +94,10 @@ define([
     var expectedMemory = new Uint8Array([
       /*  0: */   16,    0,    0,    0,    2,    0,    0,    0,
       /*  8: */   31,    0,    0,    0,    0,    0,    0,    0,
-      /* 16: */   72,    0,    0,    0,   12,    0,    0,    0,
+      /* 16: */   80,    0,    0,    0,   13,    0,    0,    0,
       /* 24: */ 0xD5, 0xB4, 0x12, 0x02, 0x93, 0x6E, 0x01,    0,
       /* 32: */    5,    0,    0,    0,    0,    0,    0,    0,
-      /* 40: */   48,    0,    0,    0,    0,    0,    0,    0,
+      /* 40: */   56,    0,    0,    0,    0,    0,    0,    0,
     ]);
     // TODO(abarth): Test more of the message's raw memory.
     var actualMemory = new Uint8Array(message.memory.buffer,