Roll Skia from ac9d3f6f07a6 to 29c70f2bb656 (3 revisions) (#19316)

https://skia.googlesource.com/skia.git/+log/ac9d3f6f07a6..29c70f2bb656

2020-06-25 johnstiles@google.com Update SkComposeColorFilter to support an input FP.
2020-06-25 jvanverth@google.com Implement Direct3D semaphores
2020-06-25 adlai@google.com Remove outdated comment

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 lovisolo@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/+doc/master/autoroll/README.md

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': 'ac9d3f6f07a6e4226c823a56c6f71e0e51d73bc1',
+  'skia_revision': '29c70f2bb656e126bf1747d60b40d428d58eae5e',
 
   # 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

-Signature: 0579cecf44e14519046bd9619b71f71d
+Signature: 244475f977c469232c5f2094e3fcde2f
 
 UNUSED LICENSES:
 
@@ -3919,6 +3919,7 @@ FILE: ../../../third_party/skia/modules/canvaskit/viewer_bindings.cpp
 FILE: ../../../third_party/skia/src/core/SkIDChangeListener.cpp
 FILE: ../../../third_party/skia/src/core/SkMatrixProvider.h
 FILE: ../../../third_party/skia/src/core/SkVM_fwd.h
+FILE: ../../../third_party/skia/src/gpu/GrBackendSemaphore.cpp
 FILE: ../../../third_party/skia/src/gpu/GrBackendSurfaceMutableStateImpl.h
 FILE: ../../../third_party/skia/src/gpu/GrBackendUtils.h
 FILE: ../../../third_party/skia/src/gpu/GrBlockAllocator.cpp
@@ -3961,6 +3962,8 @@ FILE: ../../../third_party/skia/src/gpu/d3d/GrD3DResourceProvider.h
 FILE: ../../../third_party/skia/src/gpu/d3d/GrD3DResourceState.h
 FILE: ../../../third_party/skia/src/gpu/d3d/GrD3DRootSignature.cpp
 FILE: ../../../third_party/skia/src/gpu/d3d/GrD3DRootSignature.h
+FILE: ../../../third_party/skia/src/gpu/d3d/GrD3DSemaphore.cpp
+FILE: ../../../third_party/skia/src/gpu/d3d/GrD3DSemaphore.h
 FILE: ../../../third_party/skia/src/gpu/d3d/GrD3DStencilAttachment.cpp
 FILE: ../../../third_party/skia/src/gpu/d3d/GrD3DStencilAttachment.h
 FILE: ../../../third_party/skia/src/gpu/d3d/GrD3DTexture.cpp