AudioBufferSourceNode loop duration should be the actual duration

AudioBufferSourceNode loop duration should be the actual duration

When an AudioBufferSourceNode is looping and the user calls
start(when, offset, duration), the source should play the loop as if
the user called start(when, offset) followed by stop(when+duration). This means there may be many repetitions of the loop if the duration is long.

See also the discussion in https://github.com/WebAudio/web-audio-api/issues/421

BUG=430991
TESTS=audiobuffersource-start,audiobuffersource-loop-comprehensive

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=189563

[Raymond Toy, 2015-02-03 19:20:41]

rtoy@chromium.org changed reviewers:
+ hongchan@chromium.org

[Raymond Toy, 2015-02-03 19:20:41]

PTAL.

[hongchan, 2015-02-03 23:09:05]

lgtm

https://codereview.chromium.org/723823002/diff/60001/LayoutTests/webaudio/aud...
File LayoutTests/webaudio/audiobuffersource-loop-comprehensive.html (right):

https://codereview.chromium.org/723823002/diff/60001/LayoutTests/webaudio/aud...
LayoutTests/webaudio/audiobuffersource-loop-comprehensive.html:97: 
I understand there are so many objects and properties in 'tests' variable,
actually it would be better for us to read if we can put one property at a line.

[Raymond Toy, 2015-02-03 23:42:56]

New patchsets have been uploaded after l-g-t-m from hongchan@chromium.org

[Raymond Toy, 2015-02-04 00:18:06]

https://codereview.chromium.org/723823002/diff/60001/LayoutTests/webaudio/aud...
File LayoutTests/webaudio/audiobuffersource-loop-comprehensive.html (right):

https://codereview.chromium.org/723823002/diff/60001/LayoutTests/webaudio/aud...
LayoutTests/webaudio/audiobuffersource-loop-comprehensive.html:97: 
On 2015/02/03 23:09:05, hoch wrote:
> I understand there are so many objects and properties in 'tests' variable,
> actually it would be better for us to read if we can put one property at a
line.

Done.

[Raymond Toy, 2015-02-04 19:07:44]

rtoy@chromium.org changed reviewers:
+ kbr@chromium.org

[Raymond Toy, 2015-02-04 19:07:45]

PTAL.

[Ken Russell (switch to Gerrit), 2015-02-04 19:48:08]

lgtm

[Raymond Toy, 2015-02-04 20:51:15]

The CQ bit was checked by rtoy@chromium.org

[commit-bot: I haz the power, 2015-02-04 20:52:10]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/723823002/80001

[commit-bot: I haz the power, 2015-02-05 15:20:41]

Committed patchset #5 (id:80001) as
https://src.chromium.org/viewvc/blink?view=rev&revision=189563