Do not set touch region on PageOverlay layer.

Do not set touch region on PageOverlay layer.

With new touch hit testing in compositor, which looks through all
the layers hitting the point, we don't need touch regions on overlay
layer anymore.

Note, that we still need main-thread scrolling to stay in sync with
page contents.

BUG=304271
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=175578

[dgozman, 2014-06-02 10:04:50]

Could you please take a look?

[Rick Byers, 2014-06-02 18:43:14]

lgtm, thanks!

[dgozman, 2014-06-04 07:48:40]

jochen@, could you please approve?

[pfeldman, 2014-06-05 12:32:38]

lgtm

[dgozman, 2014-06-05 12:32:57]

The CQ bit was checked by dgozman@chromium.org

[commit-bot: I haz the power, 2014-06-05 12:33:08]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/dgozman@chromium.org/305383002/1

[commit-bot: I haz the power, 2014-06-05 14:07:09]

FYI, CQ is re-trying this CL (attempt #1).
The failing builders are:
  mac_blink_rel on tryserver.blink
(http://build.chromium.org/p/tryserver.blink/builders/mac_blink_rel/builds/10424)

[commit-bot: I haz the power, 2014-06-05 14:42:03]

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

[commit-bot: I haz the power, 2014-06-05 14:42:03]

Try jobs failed on following builders:
  mac_blink_rel on tryserver.blink
(http://build.chromium.org/p/tryserver.blink/builders/mac_blink_rel/builds/10435)

[dgozman, 2014-06-05 14:45:36]

The CQ bit was checked by dgozman@chromium.org

[commit-bot: I haz the power, 2014-06-05 14:45:56]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/dgozman@chromium.org/305383002/1

[commit-bot: I haz the power, 2014-06-05 15:21:09]

Change committed as 175578