Revert "remove unused SkMeshUtils and SkBoundaryPatch"

This reverts commit 5e21e0991968271ee37f446de7e08620ad1b50bb.

Reason for revert: Breaks Pdfium build see:
    https://chromium-swarm.appspot.com/task?id=3504e60d4bc10810&refresh=10

Original change's description:
> remove unused SkMeshUtils and SkBoundaryPatch
> 
> BUG=skia:6366
> 
> Change-Id: Ibacd397e0a246dbeefde074c98712ada3848a7b6
> Reviewed-on: https://skia-review.googlesource.com/9852
> Reviewed-by: Mike Reed <reed@google.com>
> Commit-Queue: Mike Reed <reed@google.com>
> 

TBR=djsollen@google.com,reed@google.com,reviews@skia.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:6366

Change-Id: I2403bae0a17bce8eeec743c6f433bb51b214e669
Reviewed-on: https://skia-review.googlesource.com/9891
Reviewed-by: Stephan Altmueller <stephana@google.com>
Commit-Queue: Stephan Altmueller <stephana@google.com>
5 files changed