Roll src/third_party/skia dc49b0ca9816..a2a0c8a2c475 (4 commits) (flutter#16197)

https://skia.googlesource.com/skia.git/+log/dc49b0ca9816..a2a0c8a2c475

git log dc49b0ca9816..a2a0c8a2c475 --date=short --first-parent --format='%ad %ae %s'
2020-01-29 reed@google.com extract font from run
2020-01-29 fmalita@chromium.org [skottie] Cleanup: remove unused header
2020-01-29 robertphillips@google.com Update wacky_yuv_formats GM to demonstrate YUV resizing on the GPU
2020-01-29 robertphillips@google.com Add SkImage::MakeTextureFromCompressed and deprecate MakeFromCompressed

Created with:
  gclient setdep -r src/third_party/skia@a2a0c8a2c475

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/skia-flutter-autoroll
Please CC reed@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

Bug: None
Tbr: reed@google.com

Author: skia-flutter-autoroll

DEPS

@@ -26,7 +26,7 @@ vars = {
   'skia_git': 'https://skia.googlesource.com',
   # OCMock is for testing only so there is no google clone
   'ocmock_git': 'https://github.com/erikdoe/ocmock.git',
-  'skia_revision': 'dc49b0ca9816207335bbe3f9c01989dfb3e5543d',
+  'skia_revision': 'a2a0c8a2c47519fea570c0179d90373c3230346d',
 
   # When updating the Dart revision, ensure that all entries that are
   # dependencies of Dart are also updated to match the entries in the

ci/licenses_golden/licenses_skia

@@ -1,4 +1,4 @@
-Signature: f3a249baaa5edd8c55bea9e6a36c8836
+Signature: 1ec037488511721f0589c3b1da312165
 
 UNUSED LICENSES:
 
@@ -3362,7 +3362,6 @@ FILE: ../../../third_party/skia/include/utils/SkTextUtils.h
 FILE: ../../../third_party/skia/infra/cts/run_testlab.go
 FILE: ../../../third_party/skia/modules/skottie/gm/3dgm.cpp
 FILE: ../../../third_party/skia/modules/skottie/include/SkottieProperty.h
-FILE: ../../../third_party/skia/modules/skottie/src/SkottieAdapter.h
 FILE: ../../../third_party/skia/modules/skottie/src/SkottieJson.cpp
 FILE: ../../../third_party/skia/modules/skottie/src/SkottieJson.h
 FILE: ../../../third_party/skia/modules/skottie/src/SkottiePriv.h