Mark required dictionary members as required

Mark required dictionary members as required

Update code to remove explicit tests for required members and update
tests accordingly.

BUG=651090
TEST=constructor/iirfilter.html

Committed: https://crrev.com/ad65d1a7dc4dcbd4578752439edd441f7fa7e81e
Cr-Commit-Position: refs/heads/master@{#424480}

[Raymond Toy, 2016-10-05 15:57:36]

The CQ bit was checked by rtoy@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-10-05 15:57:53]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-10-05 17:17:19]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-10-05 17:17:20]

Dry run: This issue passed the CQ dry run.

[Raymond Toy, 2016-10-06 00:39:18]

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

[Raymond Toy, 2016-10-06 00:39:18]

PTAL

[hongchan, 2016-10-06 17:52:47]

lgtm

[Raymond Toy, 2016-10-07 15:45:59]

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

[Raymond Toy, 2016-10-07 15:46:00]

tkent: PTAL as API owner

A minor tweak to the IDL to mark required dictionary members as required.  I
don't think users will notice a change except that the error message will be
different. (We previously checked in the code for required members.)

[tkent, 2016-10-11 13:53:42]

lgtm

[Raymond Toy, 2016-10-11 15:39:26]

The CQ bit was checked by rtoy@chromium.org

[commit-bot: I haz the power, 2016-10-11 15:40:01]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-10-11 17:53:43]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-10-11 17:55:20]

Description was changed from

==========
Mark required dictionary members as required

Update code to remove explicit tests for required members and update
tests accordingly.

BUG=651090
TEST=constructor/iirfilter.html
==========

to

==========
Mark required dictionary members as required

Update code to remove explicit tests for required members and update
tests accordingly.

BUG=651090
TEST=constructor/iirfilter.html

Committed: https://crrev.com/ad65d1a7dc4dcbd4578752439edd441f7fa7e81e
Cr-Commit-Position: refs/heads/master@{#424480}
==========

[commit-bot: I haz the power, 2016-10-11 17:55:21]

Patchset 1 (id:??) landed as
https://crrev.com/ad65d1a7dc4dcbd4578752439edd441f7fa7e81e
Cr-Commit-Position: refs/heads/master@{#424480}