[DevTools] More Device Mode polish.

[DevTools] More Device Mode polish.

- fixed ruler in overlay with page scale factor;
- dimming zoom label based on some content being cropped;
- added dpr and ua type labels;
- fixed fit calculations;
- string updates.

BUG=540864
Committed: https://crrev.com/a15860e14bdca7cba13cad960008e0581836b93b
Cr-Commit-Position: refs/heads/master@{#368822}

[dgozman, 2016-01-12 02:20:09]

dgozman@chromium.org changed reviewers:
+ pfeldman@chromium.org

[dgozman, 2016-01-12 02:20:10]

Take a look please.

[pfeldman, 2016-01-12 02:24:36]

lgtm

[dgozman, 2016-01-12 05:47:47]

The CQ bit was checked by dgozman@chromium.org

[commit-bot: I haz the power, 2016-01-12 05:47:58]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1575203003/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1575203003/1

[commit-bot: I haz the power, 2016-01-12 08:40:31]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-01-12 08:42:45]

Description was changed from

==========
[DevTools] More Device Mode polish.

- fixed ruler in overlay with page scale factor;
- dimming zoom label based on some content being cropped;
- added dpr and ua type labels;
- fixed fit calculations;
- string updates.

BUG=540864
==========

to

==========
[DevTools] More Device Mode polish.

- fixed ruler in overlay with page scale factor;
- dimming zoom label based on some content being cropped;
- added dpr and ua type labels;
- fixed fit calculations;
- string updates.

BUG=540864

Committed: https://crrev.com/a15860e14bdca7cba13cad960008e0581836b93b
Cr-Commit-Position: refs/heads/master@{#368822}
==========

[commit-bot: I haz the power, 2016-01-12 08:42:46]

Patchset 1 (id:??) landed as
https://crrev.com/a15860e14bdca7cba13cad960008e0581836b93b
Cr-Commit-Position: refs/heads/master@{#368822}

[pfeldman, 2016-01-12 19:34:27]

A revert of this CL (patchset #1 id:1) has been created in
https://codereview.chromium.org/1574373002/ by pfeldman@chromium.org.

The reason for reverting is: Breaks responsive mode..