Merge third_party/skia/src from https://chromium.googlesource.com/external/skia/src.git at c54179f4375f836f4e53a9de6367e596e94d6e9d

This commit was generated by merge_from_chromium.py.

Change-Id: Iaaa720438124aea9957ddb67f8e0f0685661b0a1