MIDI{Input, Output}Map[Symbol.iterator]() should return entries.

MIDI{Input, Output}Map[Symbol.iterator]() should return entries.

ES6 Map returns `entries' method when [@@iterator] property is required[1].
MIDIInputMap and MIDIOutputMap should do the same.

1: https://people.mozilla.org/~jorendorff/es6-draft.html#sec-map.prototype-@@iterator

BUG=341423
R=toyoshim@chromium.org

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=181616

[yhirano, 2014-09-09 03:56:01]

PTAL

I thought that Map.prototype[@@iterator]() returns values, but it was wrong.
Currently MIDI{Input, Output}Map don't have [@@iterator] property in the spec,
but some people([1], [2]) wants to mimic ES6 Map here.

1: https://github.com/WebAudio/web-midi-api/issues/91#issuecomment-52328166
2: https://github.com/WebAudio/web-midi-api/issues/91#issuecomment-54916191

[Takashi Toyoshima, 2014-09-09 05:06:28]

lgtm with one quick question

https://codereview.chromium.org/555683003/diff/20001/LayoutTests/webmidi/requ...
File LayoutTests/webmidi/requestmidiaccess.html (right):

https://codereview.chromium.org/555683003/diff/20001/LayoutTests/webmidi/requ...
LayoutTests/webmidi/requestmidiaccess.html:16: debug("for (var input of
inputs.values())");
Are these debug() lines are intended changes?

[yhirano, 2014-09-09 05:14:47]

https://codereview.chromium.org/555683003/diff/20001/LayoutTests/webmidi/requ...
File LayoutTests/webmidi/requestmidiaccess.html (right):

https://codereview.chromium.org/555683003/diff/20001/LayoutTests/webmidi/requ...
LayoutTests/webmidi/requestmidiaccess.html:16: debug("for (var input of
inputs.values())");
On 2014/09/09 05:06:28, Takashi Toyoshima (chromium) wrote:
> Are these debug() lines are intended changes?

I added "for (... of inputs.entries())" to distinguish entries between
inputs.entries() and inputs[@@iterator](). Without the mark, the test pass
accidentally when inputs.entries() returns [entry, entry] and
inputs[@@iterator]() returns []. 
I added other marks for consistency.

[Takashi Toyoshima, 2014-09-09 05:27:48]

I see.
Thank you for clarification.

[yhirano, 2014-09-09 06:50:51]

The CQ bit was checked by yhirano@chromium.org

[commit-bot: I haz the power, 2014-09-09 06:51:30]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/yhirano@chromium.org/555683003/20001

[commit-bot: I haz the power, 2014-09-09 07:52:47]

Committed patchset #2 (id:20001) as 181616