Add sRGB support to monobench.

We'll now run non-rendering and raster benchmarks,
for simplicity choosing sRGB as the only raster configuration.

$ ninja -C out monobench; and out/monobench "linear_clamp_(3color|pos)\$"
    gradient_linear_clamp_…
    6257  …3color 1x  …pos 1.03x

$ ninja -C out monobench; and out/monobench "linear_clamp_.*[^4][^f]\$"
    gradient_linear_clamp_…
    321  …shallow 1x  …shallow_dither 1x  …3color 1.49x  …hicolor 1.5x  …pos 1.52x

Change-Id: I7282a84c982eb1f11f0ea2dfe39afea66231761c
Reviewed-on: https://skia-review.googlesource.com/16877
Reviewed-by: Herb Derby <herb@google.com>
Commit-Queue: Mike Klein <mtklein@chromium.org>
1 file changed