NodeFilter acceptNode return type changed to unsigned

NodeFilter acceptNode return type changed to unsigned

acceptNode return type was set to short. It has been 
updated to return unsigned. acceptNode returns enum 
value and thus change is more to comply with the
 specification without much impact. 

The usage in the NodeIterator and TreeWalker was also 
expecting short return value and has been updated to
unsigned.  

BUG=496400
R=philipj, rbyers

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=197693

[Habib Virji, 2015-06-19 13:35:26]

The CQ bit was checked by habib.virji@samsung.com to run a CQ dry run

[commit-bot: I haz the power, 2015-06-19 13:35:51]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1197723002/1

[commit-bot: I haz the power, 2015-06-19 15:05:09]

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

[commit-bot: I haz the power, 2015-06-19 15:05:10]

Dry run: Try jobs failed on following builders:
  mac_blink_rel on tryserver.blink (JOB_FAILED,
http://build.chromium.org/p/tryserver.blink/builders/mac_blink_rel/builds/59774)

[Habib Virji, 2015-06-22 15:40:21]

The CQ bit was checked by habib.virji@samsung.com to run a CQ dry run

[commit-bot: I haz the power, 2015-06-22 15:41:05]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1197723002/20001

[commit-bot: I haz the power, 2015-06-22 16:34:25]

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

[commit-bot: I haz the power, 2015-06-22 16:34:26]

Dry run: This issue passed the CQ dry run.

[Habib Virji, 2015-06-23 08:13:01]

habib.virji@samsung.com changed reviewers:
+ rbyers@chromium.org

[Habib Virji, 2015-06-23 08:13:49]

PTAL.

[Rick Byers, 2015-06-23 21:06:10]

rbyers@chromium.org changed reviewers:
+ tkent@chromium.org
- philipj@opera.com, rbyers@chromium.org

[Rick Byers, 2015-06-23 21:08:50]

We should probably get an OWNER from DOM-team for all these DOM API tweaks (I
don't really have any context, sorry).  tkent is probably your best bet.

[tkent, 2015-06-23 23:22:02]

The CQ bit was checked by tkent@chromium.org

[tkent, 2015-06-23 23:22:03]

lgtm

[commit-bot: I haz the power, 2015-06-23 23:22:36]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1197723002/20001

[commit-bot: I haz the power, 2015-06-24 02:00:40]

Committed patchset #2 (id:20001) as
https://src.chromium.org/viewvc/blink?view=rev&revision=197693