Add back raster pipeline image tiling guard

(SK_SUPPORT_LEGACY_TILED_BITMAPS)

We have a couple of M61 regressions related to this change.  Adding the
guard back in case we decide to revert.

TBR=
Change-Id: I0703e61d70aa919b71ff9711ec28bcfc67e3e84a
Reviewed-on: https://skia-review.googlesource.com/36120
Reviewed-by: Florin Malita <fmalita@chromium.org>
Commit-Queue: Florin Malita <fmalita@chromium.org>
1 file changed