Roll Fuchsia Mac Toolchain from...

Roll Fuchsia Mac Toolchain from git_revision:7d48eff8ba172216fca3649a3c452de4c7c16c00 to 139p8dSfW... (#23936)

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/fuchsia-mac-toolchain-flutter-engine
Please CC zra@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

@@ -504,7 +504,7 @@ deps = {
     'packages': [
       {
         'package': 'fuchsia/third_party/clang/mac-amd64',
-        'version': 'git_revision:7d48eff8ba172216fca3649a3c452de4c7c16c00' 
+        'version': '139p8dSfWkDS3XU7olg1SCcPowC4MokiYUR5u2aqDOMC' 
       }
     ],
     'condition': 'host_os == "mac"',