Always round text position correctly.

Always round text position correctly.

Will require SK_IGNORE_SUBPIXEL_AXIS_ALIGN_FIX to be added to Chromium's skia.gyp.

[bungeman, 2013-02-22 18:43:12]

This is a first step toward fixing issues where text does not always move in
step with content and underlines.

The meat of this change is that when the request for subpixel is ignored (for
snapping) on a given axis, the positioning of the text takes this into account.
This is currently guarded by '#ifndef SK_IGNORE_SUBPIXEL_AXIS_ALIGN_FIX' as it
will require ~150 layout tests to be rebaselined.

The effect of this change in Chromium is that text will move more in step with
the content. Text decorations will need a separate fix as they currently do not
move in step with other content (or text, for that matter).

[reed1, 2013-02-22 20:30:49]

1. push the build-flag to the top of the CL desc, so the DEPS roller will see it
2. if we're sure that that build-flag, when defined, will *not* change any
results, lgtm

[bungeman, 2013-02-25 15:59:01]

Committed revision 7842.