WebVR: fix angular velocity calculation for headset

WebVR: fix angular velocity calculation for headset

The refactor https://chromium-review.googlesource.com/536475 lost a pair of
parentheses, so the division by epsilon_seconds was just dividing one of the
matrix elements instead of the difference. This broke angular velocity
calculation.

BUG=735155
Review-Url: https://codereview.chromium.org/2947843003
Cr-Commit-Position: refs/heads/master@{#480946}
Committed: https://chromium.googlesource.com/chromium/src/+/455a29452a85a4de9603b0d4d99373930cb20bb3

[klausw, 2017-06-20 19:25:11]

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

[mthiesse, 2017-06-20 19:33:08]

lgtm

[mthiesse, 2017-06-20 19:33:11]

The CQ bit was checked by mthiesse@chromium.org

[commit-bot: I haz the power, 2017-06-20 19:34:00]

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, 2017-06-20 20:44:42]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1497987191859280, "parent_rev":
"1237ccfd0b8ab9a9cb7921076996429222e1759b", "commit_rev":
"455a29452a85a4de9603b0d4d99373930cb20bb3"}

[commit-bot: I haz the power, 2017-06-20 20:44:56]

Description was changed from

==========
WebVR: fix angular velocity calculation for headset

The refactor https://chromium-review.googlesource.com/536475 lost a pair of
parentheses, so the division by epsilon_seconds was just dividing one of the
matrix elements instead of the difference. This broke angular velocity
calculation.

BUG=735155
==========

to

==========
WebVR: fix angular velocity calculation for headset

The refactor https://chromium-review.googlesource.com/536475 lost a pair of
parentheses, so the division by epsilon_seconds was just dividing one of the
matrix elements instead of the difference. This broke angular velocity
calculation.

BUG=735155

Review-Url: https://codereview.chromium.org/2947843003
Cr-Commit-Position: refs/heads/master@{#480946}
Committed:
https://chromium.googlesource.com/chromium/src/+/455a29452a85a4de9603b0d4d993...
==========

[commit-bot: I haz the power, 2017-06-20 20:44:57]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/455a29452a85a4de9603b0d4d993...