Roll Skia from 943f70d6f836 to 18bd238c3db9 (2 revisions) (flutter/engine#42755)

https://skia.googlesource.com/skia.git/+log/943f70d6f836..18bd238c3db9

2023-06-12 skia-autoroll@skia-public.iam.gserviceaccount.com Roll SK Tool from c5beac3c360b to 5c0eef0be6b9
2023-06-12 skia-autoroll@skia-public.iam.gserviceaccount.com Roll ANGLE from 8a62b4c44fc9 to 10380f4ba473 (12 revisions)

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 brianosman@google.com,herb@google.com,jacksongardner@google.com,rmistry@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': '943f70d6f836f6f1b7b7b542585425a63fb262ca',
+  'skia_revision': '18bd238c3db92943911132ca69ed405fac2c9218',
 
   # WARNING: DO NOT EDIT canvaskit_cipd_instance MANUALLY
   # See `lib/web_ui/README.md` for how to roll CanvasKit to a new version.