clean up for removing drawTextOnPath from canvas

Docs-Preview: https://skia.org/?cl=150127
Bug: skia:7554
Change-Id: I4aa980e083626e25c2f04d8e18a75bdc280b5191
Reviewed-on: https://skia-review.googlesource.com/150127
Reviewed-by: Florin Malita <fmalita@chromium.org>
Commit-Queue: Mike Reed <reed@google.com>
4 files changed