Roll Skia from 9e77f20864d3 to 311dd9d8474c (4 revisions) (flutter#20493)

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': '9e77f20864d372d303e4b0bdd7d32da1221b56e6',
+  'skia_revision': '311dd9d8474c0a152ee6369d3ddce02be3744480',
 
   # 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: 749cd1dd70600580a84bc34de0debf82
+Signature: 08e9d54647e7018526cf6c5e7a1f6ab0
 
 UNUSED LICENSES:
 
@@ -4257,9 +4257,9 @@ FILE: ../../../third_party/skia/docs/examples/Canvas_drawVertices.cpp
 FILE: ../../../third_party/skia/docs/examples/Canvas_drawVertices_2.cpp
 FILE: ../../../third_party/skia/docs/examples/Canvas_empty_constructor.cpp
 FILE: ../../../third_party/skia/docs/examples/Canvas_getBaseLayerSize.cpp
+FILE: ../../../third_party/skia/docs/examples/Canvas_getContext.cpp
 FILE: ../../../third_party/skia/docs/examples/Canvas_getDeviceClipBounds.cpp
 FILE: ../../../third_party/skia/docs/examples/Canvas_getDeviceClipBounds_2.cpp
-FILE: ../../../third_party/skia/docs/examples/Canvas_getGrContext.cpp
 FILE: ../../../third_party/skia/docs/examples/Canvas_getLocalClipBounds.cpp
 FILE: ../../../third_party/skia/docs/examples/Canvas_getLocalClipBounds_2.cpp
 FILE: ../../../third_party/skia/docs/examples/Canvas_getProps.cpp