Roll src/third_party/skia 4c3b63e289c5..71fe8baccc01 (3 commits) (flutter#5940)

Auto-roller completed checks. Merging.

Author: skia-flutter-autoroll

DEPS

@@ -23,7 +23,7 @@ vars = {
   'fuchsia_git': 'https://fuchsia.googlesource.com',
   'github_git': 'https://github.com',
   'skia_git': 'https://skia.googlesource.com',
-  'skia_revision': '4c3b63e289c58465d92a1ccec7170c89ffa8d3e0',
+  'skia_revision': '71fe8baccc01c9500fa258964dc0504eb4d661be',
 
   # When updating the Dart revision, ensure that all entries that are
   # dependencies of Dart are also updated to match the entries in the

travis/licenses_golden/licenses_skia

@@ -1,4 +1,4 @@
-Signature: 92f0ccfba5adbc2142e4f4594dfd9029
+Signature: 6ae027f2b5f223bf74067fdaf35d555b
 
 UNUSED LICENSES:
 
@@ -2770,12 +2770,10 @@ FILE: ../../../third_party/skia/src/gpu/GrGpuResourceCacheAccess.h
 FILE: ../../../third_party/skia/src/gpu/GrPathRendering.cpp
 FILE: ../../../third_party/skia/src/gpu/GrPathRendering.h
 FILE: ../../../third_party/skia/src/gpu/GrPendingIOResource.h
-FILE: ../../../third_party/skia/src/gpu/GrPendingProgramElement.h
 FILE: ../../../third_party/skia/src/gpu/GrPrimitiveProcessor.cpp
 FILE: ../../../third_party/skia/src/gpu/GrProcessorAnalysis.cpp
 FILE: ../../../third_party/skia/src/gpu/GrProcessorAnalysis.h
 FILE: ../../../third_party/skia/src/gpu/GrProgramDesc.h
-FILE: ../../../third_party/skia/src/gpu/GrProgramElement.h
 FILE: ../../../third_party/skia/src/gpu/GrRectanizer_pow2.h
 FILE: ../../../third_party/skia/src/gpu/GrRectanizer_skyline.h
 FILE: ../../../third_party/skia/src/gpu/GrResourceCache.cpp