Don't set page scale limits inside EventSender::setPageScaleFactor.

Don't set page scale limits inside EventSender::setPageScaleFactor.

This prevents proper testing of pinch-zoom as the limits change on every zoom
and limits are used to calculate the main frame size in virtual-viewport pinch
to zoom. This is part of a 3-sided patch:

1) Add a setPageScaleFactorLimits to EventSender
2) Change existing layout tests that use setPageScaleFactor to use this method
   to set up the limits.
3) This patch removes the setPageScaleLimits call inside setPageScaleFactor.

BUG=435151
Committed: https://crrev.com/323f0ecd1c35e0e0588afcdc1178709af99e3b60
Cr-Commit-Position: refs/heads/master@{#305084}

[bokan, 2014-11-19 16:38:47]

bokan@chromium.org changed reviewers:
+ dpranke@chromium.org

[Dirk Pranke, 2014-11-19 22:28:28]

lgtm

[bokan, 2014-11-20 21:13:22]

The CQ bit was checked by bokan@chromium.org

[commit-bot: I haz the power, 2014-11-20 21:14:42]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/738463003/1

[commit-bot: I haz the power, 2014-11-20 22:04:04]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2014-11-20 22:04:55]

Patchset 1 (id:??) landed as
https://crrev.com/323f0ecd1c35e0e0588afcdc1178709af99e3b60
Cr-Commit-Position: refs/heads/master@{#305084}