Merge third_party/skia/gyp from https://chromium.googlesource.com/external/skia/gyp.git at ad64fe80988d6bd5b1467ecfab1341bc71aab706

This commit was generated by merge_from_chromium.py.

Change-Id: I177ddac7f30e748c08cd13acb57fc7a8c26790ab