Add back DCHECK for pointer type in PointerEventFactory

Add back DCHECK for pointer type in PointerEventFactory

This DCHECK was originally commented here
https://codereview.chromium.org/2659523004/

and after the fix landed here
https://codereview.chromium.org/2688793003/

but it got mistakenly reverted due to crbug.com/694742
which had nothing to do with this DCHECK. So this
re-re-enables this pointertype DCHECK for coalesced
pointer events.

BUG=684292
Review-Url: https://codereview.chromium.org/2722643002
Cr-Commit-Position: refs/heads/master@{#453603}
Committed: https://chromium.googlesource.com/chromium/src/+/ef2a8e07616635ec90e8b30a95fb8a43a7f0ec9a

[Navid Zolghadr, 2017-02-27 20:42:11]

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

[commit-bot: I haz the power, 2017-02-27 20:42:50]

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

[Navid Zolghadr, 2017-02-27 20:43:35]

nzolghadr@chromium.org changed reviewers:
+ bokan@chromium.org

[commit-bot: I haz the power, 2017-02-27 22:10:43]

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

[commit-bot: I haz the power, 2017-02-27 22:10:44]

Dry run: This issue passed the CQ dry run.

[bokan, 2017-02-27 22:48:44]

lgtm

[Navid Zolghadr, 2017-02-28 15:16:53]

The CQ bit was checked by nzolghadr@chromium.org

[commit-bot: I haz the power, 2017-02-28 15:17:08]

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, 2017-02-28 15:20:26]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1488295013454430, "parent_rev":
"ffae7e0a3390a6f07620f47f95d5d00a0a887f66", "commit_rev":
"ef2a8e07616635ec90e8b30a95fb8a43a7f0ec9a"}

[commit-bot: I haz the power, 2017-02-28 15:21:01]

Description was changed from

==========
Add back DCHECK for pointer type in PointerEventFactory

This DCHECK was originally commented here
https://codereview.chromium.org/2659523004/

and after the fix landed here
https://codereview.chromium.org/2688793003/

but it got mistakenly reverted due to crbug.com/694742
which had nothing to do with this DCHECK. So this
re-re-enables this pointertype DCHECK for coalesced
pointer events.

BUG=684292
==========

to

==========
Add back DCHECK for pointer type in PointerEventFactory

This DCHECK was originally commented here
https://codereview.chromium.org/2659523004/

and after the fix landed here
https://codereview.chromium.org/2688793003/

but it got mistakenly reverted due to crbug.com/694742
which had nothing to do with this DCHECK. So this
re-re-enables this pointertype DCHECK for coalesced
pointer events.

BUG=684292

Review-Url: https://codereview.chromium.org/2722643002
Cr-Commit-Position: refs/heads/master@{#453603}
Committed:
https://chromium.googlesource.com/chromium/src/+/ef2a8e07616635ec90e8b30a95fb...
==========

[commit-bot: I haz the power, 2017-02-28 15:21:02]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/ef2a8e07616635ec90e8b30a95fb...