Simplify SkShader::ContextRec::fLocalMatrix handling

Minor cleanup.

R=robertphillips@google.com,reed@google.com

Change-Id: I1a27af61e3e3bb5e895c9a3265da6b0408234165
Reviewed-on: https://skia-review.googlesource.com/7632
Commit-Queue: Florin Malita <fmalita@chromium.org>
Reviewed-by: Robert Phillips <robertphillips@google.com>
3 files changed