Refactor TouchTransformerConverter to allow support for Ozone

Refactor TouchTransformerConverter to allow support for Ozone

In Ozone the touch events are received in device coordinates. This
change consolidates the different transformations into one function and
makes it use the touchscreen size when computing the transformation for
Ozone and the framebuffer size for X11.

BUG=425258
TESTS=Manually verified that X11 in single, mirror, extended and docked
mode work with external touchscreen.

Committed: https://crrev.com/8c3bd1e68124be19b17420144b4b76ece0c87035
Cr-Commit-Position: refs/heads/master@{#302135}

[dnicoara, 2014-10-30 16:34:20]

dnicoara@chromium.org changed reviewers:
+ derat@chromium.org, miletus@chromium.org

[dnicoara, 2014-10-30 16:34:21]

PTAL

derat@ for OWNERS

[Daniel Erat, 2014-10-30 16:38:08]

lgtm as an owner, although i didn't review the math

[dnicoara, 2014-10-30 16:49:19]

On 2014/10/30 16:38:08, Daniel Erat wrote:
> lgtm as an owner, although i didn't review the math

Thanks, the math shouldn't have changed since I just re-used the existing parts.
But just in case, Yufeng would you mind going over the math in detail?

[Yufeng Shen (Slow to review), 2014-10-30 17:19:14]

On 2014/10/30 16:49:19, dnicoara wrote:
> On 2014/10/30 16:38:08, Daniel Erat wrote:
> > lgtm as an owner, although i didn't review the math
> 
> Thanks, the math shouldn't have changed since I just re-used the existing
parts.
> But just in case, Yufeng would you mind going over the math in detail?

lgtm.

If the unittests pass, then the math is correct.

[dnicoara, 2014-10-30 18:29:57]

The CQ bit was checked by dnicoara@chromium.org

[commit-bot: I haz the power, 2014-10-30 18:31:25]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/688183002/20001

[commit-bot: I haz the power, 2014-10-30 19:53:47]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2014-10-30 19:54:58]

Patchset 2 (id:??) landed as
https://crrev.com/8c3bd1e68124be19b17420144b4b76ece0c87035
Cr-Commit-Position: refs/heads/master@{#302135}