[SurfaceFlinger] Add hwc information to winscope:

* String blob of HWC dump
* Fill in HWC composition enum

Caveat is that only the primary display information is filled in.

Bug: 119443475
Test: Winscope trace
Change-Id: I246dc8df5e16388d8e58afeabfe944b158e1a39d
8 files changed