Fixed visibility check in winscope.

Changed visibility reasoning to check for bufferTransform validity only
when activeBuffer is valid. Also separated reasoning for
transforms and bufferTransforms.

Test: yarn run dev then run a trace file.
Change-Id: I6ed2065c2f316019d9dde41a613b02c311c705e4
Merged-In: I6ed2065c2f316019d9dde41a613b02c311c705e4
1 file changed