Roll src/third_party/skia/ 56586b6f3..0f7748ab3 (4 commits).

https://chromium.googlesource.com/skia.git/+log/56586b6f3dc8..0f7748ab388c

$ git log 56586b6f3..0f7748ab3 --date=short --no-merges --format='%ad %ae %s'
2016-07-25 mtklein DM: print which task caused the crash.
2016-07-25 bungeman Add test for typeface style round trip.
2016-07-25 mtklein Have SkRasterPipelineBlitter take over for F16 when it can.
2016-07-25 reed lock special-raster while the caller's bitmap is in-scope

CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_blink_rel
TBR=tomhudson@google.com

Review-Url: https://codereview.chromium.org/2184483002
Cr-Commit-Position: refs/heads/master@{#407652}

DEPS

@@ -36,7 +36,7 @@ vars = {
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling Skia
   # and whatever else without interference from each other.
-  'skia_revision': '56586b6f3dc824431958946ac8c27f0c0b564a3d',
+  'skia_revision': '0f7748ab388c3a07b71e41d8042313b6744f3cae',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling V8
   # and whatever else without interference from each other.