Roll Skia from ece9f3a15b08 to 71e40cc0faf6 (1 revision) (flutter/engine#45575)

https://skia.googlesource.com/skia.git/+log/ece9f3a15b08..71e40cc0faf6

2023-09-08 johnstiles@google.com Remove synthetic assignment to sk_FragColor outside of skslc.

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 armansito@google.com,brianosman@google.com,rmistry@google.com,zra@google.com on the revert to ensure that a human
is aware of the problem.

To file a bug in Skia: https://bugs.chromium.org/p/skia/issues/entry
To file a bug in Flutter: https://github.com/flutter/flutter/issues/new/choose

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/main/autoroll/README.md

DEPS

@@ -18,7 +18,7 @@ vars = {
   'llvm_git': 'https://llvm.googlesource.com',
   # OCMock is for testing only so there is no google clone
   'ocmock_git': 'https://github.com/erikdoe/ocmock.git',
-  'skia_revision': 'ece9f3a15b08508e3c6e9fc0aced17638b6011e4',
+  'skia_revision': '71e40cc0faf64dd30db3548ef74198bf1f54137f',
 
   # WARNING: DO NOT EDIT canvaskit_cipd_instance MANUALLY
   # See `lib/web_ui/README.md` for how to roll CanvasKit to a new version.

engine/src/flutter/ci/licenses_golden/licenses_skia

@@ -1,4 +1,4 @@
-Signature: 55dbd3aa46dc25e816ae8fc96622bc2a
+Signature: b7aec7374e9eecb93f1d5ae6a1ccbaf5
 
 ====================================================================================================
 LIBRARY: etc1