Auto-dark mode prototype

Experimental force_dark prototype mode. Enabled
by setting debug.hwui.force_dark to true.

Test: verified nothing changes without prop being set

Change-Id: Ib02f3f1a9c591cab1f312b827451f04c782c2f41
diff --git a/libs/hwui/Android.bp b/libs/hwui/Android.bp
index 0db7799..111094b 100644
--- a/libs/hwui/Android.bp
+++ b/libs/hwui/Android.bp
@@ -198,6 +198,7 @@
         "AnimatorManager.cpp",
         "Caches.cpp",
         "CanvasState.cpp",
+        "CanvasTransform.cpp",
         "ClipArea.cpp",
         "DamageAccumulator.cpp",
         "DeferredLayerUpdater.cpp",