Prevent repeated VRDisplay.requestPresent calls from spamming the device

Prevent repeated VRDisplay.requestPresent calls from spamming the device

With this patch new requestPresent calls that are made while the first one is
still pending will simply be queued up Blink-side and all resolved at once when
the original request succeeds or fails.

BUG=670441
Committed: https://crrev.com/dd2fff71ca63ff58973e36c6f411a78f04bcc7fb
Cr-Commit-Position: refs/heads/master@{#436132}

[bajones, 2016-12-02 23:29:32]

bajones@chromium.org changed reviewers:
+ klausw@chromium.org

[bajones, 2016-12-02 23:29:33]

PTAL. Fixes the issue with multiple requestPresent calls in quick succession
causing us to get invalid poses.

[klausw, 2016-12-02 23:33:52]

LGTM!

[bajones, 2016-12-02 23:41:00]

The CQ bit was checked by bajones@chromium.org

[commit-bot: I haz the power, 2016-12-02 23:41:44]

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, 2016-12-03 01:37:09]

CQ is committing da patch.

Bot data: {"patchset_id": 20001, "attempt_start_ts": 1480722060427180,
"parent_rev": "d79e82fcefb450d9ab3c7ca0760a10f5c64094fc", "commit_rev":
"e836c9ddf2a82ccd4e8a5070ecb3dda31c9197a0"}

[commit-bot: I haz the power, 2016-12-03 01:37:35]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2016-12-03 01:39:47]

Description was changed from

==========
Prevent repeated VRDisplay.requestPresent calls from spamming the device

With this patch new requestPresent calls that are made while the first one is
still pending will simply be queued up Blink-side and all resolved at once when
the original request succeeds or fails.

BUG=670441
==========

to

==========
Prevent repeated VRDisplay.requestPresent calls from spamming the device

With this patch new requestPresent calls that are made while the first one is
still pending will simply be queued up Blink-side and all resolved at once when
the original request succeeds or fails.

BUG=670441

Committed: https://crrev.com/dd2fff71ca63ff58973e36c6f411a78f04bcc7fb
Cr-Commit-Position: refs/heads/master@{#436132}
==========

[commit-bot: I haz the power, 2016-12-03 01:39:48]

Patchset 2 (id:??) landed as
https://crrev.com/dd2fff71ca63ff58973e36c6f411a78f04bcc7fb
Cr-Commit-Position: refs/heads/master@{#436132}