Log Message:
webkit-gtk: Update to 2.30.2

Changes:
2.30.2
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 - Fix scrolling when smooth scrolling is enabled in async scrolling mode.
 - Fix WebSocket requests with same-site cookies.
 - Fix TLS certificate information for service workers.
 - Handle chassis type when its value is quoted.
 - Fix the build with ENABLE_MEDIA_STREAM enabled and ENABLE_WEB_RTC_DISABLED.
 - Fix the build with ENABLE_GAMEPAD enabled.
 - Fix several crashes and rendering issues.