Account for device scale factor in automation API bounding boxes.

Account for device scale factor in automation API bounding boxes.

Bounding boxes from web pages were including the device scale factor
and all other bounding boxes were not. Fix this in the automation API
so that everything ChromeVox deals with is consistently "CSS pixels",
i.e. without the device scale factor applied.

Since we want to apply this factor for some AX trees but not others,
I took this opportunity to consolidate a few "magic constants" and
have a single shared constant for the desktop tree across the
automation API.

BUG=638701
Committed: https://crrev.com/855770d4a1e3c30a3d08f512043b9c04966922e2
Cr-Commit-Position: refs/heads/master@{#421937}

[dmazzoni, 2016-09-27 17:36:14]

dmazzoni@chromium.org changed reviewers:
+ aboxhall@chromium.org, rockot@chromium.org

[aboxhall, 2016-09-27 18:43:59]

lgtm

- is this testable? Definitely not going to block on that, just curious.

[dmazzoni, 2016-09-27 18:54:08]

The reason it's nontrivial to test is that all of the automation
tests are API tests written in JS, and there's no way to
modify the device scale factor from there.

[Ken Rockot(use gerrit already), 2016-09-27 18:57:41]

lgtm

[dmazzoni, 2016-09-29 20:41:59]

The CQ bit was checked by dmazzoni@chromium.org

[commit-bot: I haz the power, 2016-09-29 20:42:16]

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, 2016-09-29 21:21:37]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-09-29 21:23:17]

Description was changed from

==========
Account for device scale factor in automation API bounding boxes.

Bounding boxes from web pages were including the device scale factor
and all other bounding boxes were not. Fix this in the automation API
so that everything ChromeVox deals with is consistently "CSS pixels",
i.e. without the device scale factor applied.

Since we want to apply this factor for some AX trees but not others,
I took this opportunity to consolidate a few "magic constants" and
have a single shared constant for the desktop tree across the
automation API.

BUG=638701
==========

to

==========
Account for device scale factor in automation API bounding boxes.

Bounding boxes from web pages were including the device scale factor
and all other bounding boxes were not. Fix this in the automation API
so that everything ChromeVox deals with is consistently "CSS pixels",
i.e. without the device scale factor applied.

Since we want to apply this factor for some AX trees but not others,
I took this opportunity to consolidate a few "magic constants" and
have a single shared constant for the desktop tree across the
automation API.

BUG=638701

Committed: https://crrev.com/855770d4a1e3c30a3d08f512043b9c04966922e2
Cr-Commit-Position: refs/heads/master@{#421937}
==========

[commit-bot: I haz the power, 2016-09-29 21:23:18]

Patchset 1 (id:??) landed as
https://crrev.com/855770d4a1e3c30a3d08f512043b9c04966922e2
Cr-Commit-Position: refs/heads/master@{#421937}