Roll skia-recipes

6815aa7 Use skia/bin/gn instead of skia/buildtools/$(PLATFORM)/gn
ef0ad89 core: Obtain the primary repo URL from the "repository" property

BUG=skia:

Change-Id: I5cd47dd47747565c141240241b1373b34d69bee5
Reviewed-on: https://skia-review.googlesource.com/7123
Commit-Queue: Eric Boren <borenet@google.com>
Reviewed-by: Ravi Mistry <rmistry@google.com>
20 files changed