Fix the SvgMask display abnormality by removing the MaskUnit implement. In Android, MaskUnit and MaskContentUnit haven't been implemented yet, so we removed the MaskUnit implement to make the SvgMask behave normally.
Test Plan
Test is available in svgDemoCases IssueFix section as Issue#236
Summary
Fix the SvgMask display abnormality by removing the MaskUnit implement. In Android, MaskUnit and MaskContentUnit haven't been implemented yet, so we removed the MaskUnit implement to make the SvgMask behave normally.
Test Plan
Test is available in svgDemoCases IssueFix section as Issue#236
Resolve https://github.com/react-native-oh-library/react-native-harmony-svg/issues/236