Revert of Change drawText() to generate positions and send to drawPosText() (patchset #4 id:60001 of https://codereview.chromium.org/653133004/)

Reason for revert:
A large number of GMs on Ubuntu12 are failing. The text layout on GPU is visibly different than that for 8888.

Original issue's description:
> Change drawText() to generate positions and send to drawPosText()
>
> The idea here is to have a central place that does layout for drawText(), and
> then always feed text through drawPosText(). This both makes all of the
> GrTextContexts consistent in drawText() output, and does a better job of
> stressing drawPosText().
>
> Because of the effect of matrices on hinting and approximation error, the
> generated text is not 100% identical to that produced by the raster pipeline.
>
> BUG=skia:2778
>
> Committed: https://skia.googlesource.com/skia/+/7851a56895c9c076f73a835a7dd51d3c6180c16f

TBR=cdalton.nvidia@gmail.com,bungeman@google.com,reed@google.com
NOTREECHECKS=true
NOTRY=true
BUG=skia:2778

Review URL: https://codereview.chromium.org/659993003
10 files changed