Revert "Revert "remove support for HWC < 1.0""

This reverts commit 6efc967ff5e0bb33a9116aee9846b041b80d0594.

Conflicts:
	services/surfaceflinger/DisplayHardware/HWComposer.cpp

This causes weird few second lag on screen-on.

Change-Id: I8b4c5b1bcec931ac10dcf2ea4bf633b765b009f7