Roll Skia from 515eb6238867 to 57a1644f0f8f (1 revision) (#166748)

https://skia.googlesource.com/skia.git/+log/515eb6238867..57a1644f0f8f

2025-04-08 danieldilan@google.com Define flag again for PNG encoding

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
jlavrova@google.com,jonahwilliams@google.com,kjlubick@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://issues.skia.org/issues/new?component=1389291&template=1850622

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+doc/main/autoroll/README.md

engine/src/flutter/ci/licenses_golden/licenses_skia

@@ -1,4 +1,4 @@
-Signature: 286a07668d9452b2304b2a250dee1f75
+Signature: 858774ac40d1c7faff1cb8dd1caf3784
 
 ====================================================================================================
 LIBRARY: etc1