Lazy load Properties::isDrawingEnabled.

Properties::isDrawingEnabled can unexpectedly return true
even if the system property debug.hwui.drawing_enabled is false,
if its called before RenderThread is created.

This commit changes the underlying logic to lazy load the
debug.hwui.drawing_enabled prop value.

Bug: 193920054
Test: call HardwareRendererCompat.isDrawingEnabled()) from a new test
Change-Id: Ib69577745c26595ed3964a4341086138dd5d34b0
(cherry picked from commit 8e1ab42f51c501949211746c46a02a7564ebf292)