SKPs-as-benches in nanobench

This is meant to replace bench_pictures.

CQ_EXTRA_TRYBOTS=tryserver.skia:Build-Mac10.7-Clang-Arm7-Release-iOS-Trybot

BUG=skia:
R=bsalomon@google.com, jcgregorio@google.com, mtklein@google.com

Author: mtklein@chromium.org

Review URL: https://codereview.chromium.org/425393004
diff --git a/gyp/bench.gyp b/gyp/bench.gyp
index d627590..2a5071a 100644
--- a/gyp/bench.gyp
+++ b/gyp/bench.gyp
@@ -38,6 +38,7 @@
       'type': 'executable',
       'sources': [
         '../bench/GMBench.cpp',
+        '../bench/SKPBench.cpp',
         '../bench/ResultsWriter.cpp',
         '../bench/nanobench.cpp',
       ],