Merge changes I5526ac86,I9a18d480,Ib2f8c04c,I966d3fd8,I618abcb4, ...

* changes:
  SF: Clean up HWComposer logging
  SF: Remember display type in DisplayData
  SF: Move getDisplayIdentificationData to HWC2::Device
  SF: Do not assume existence of primary display
  SF: Remove DisplayDeviceState::isValid
  SF: Decouple EventThread from DisplayDevice
  SF: Clean up remaining display identifiers
  SF: Remove DisplayData constructor/destructor