Bug 915729 - Add mixed HWC and GPU Composition. r=ncameron, r=dwilson
Bug 920654 - Enable plane alpha support for HWC layers in newer H/W Composer. r=mwu, r=dwilson
Bug 927201 - Add null check before trying to close observer service. r=mrbkap
Bug 926553 - Reduce the number of items in test_arrays.html to avoid timeouts indebug B2G emulators. r=ehsan