Merge changes Icf7cf2fd,I325521b7,Ia80c865d,I73599f62,I8526e671, ... into pi-dev
* changes:
SF: Use display device factory in unit test
SF: Introduce mock::NativeWindowSurface
SF: Refactor display device creation
SF: Introduce mock::NativeWindow
SF: Introduce mock::DisplaySurface
SF: Introduce mock::EventControlThread
SF: Separate EventControlThread into interface and impl
SF: Define mock::SurfaceInterceptor
SF: Separate SurfaceInterceptor into interface and impl
SF: Define mock::MessageQueue
SF: Separate MessageQueue into interface and impl
SF: libsurfaceflinger_unittest should skip SF ctor
SF: Switch to internal display setup