Initial refactoring to enable the addition of the SkiaOpenGLPipeline.

Test: existing and new HWUI unit tests all pass.
Change-Id: I4f5c1dc839a2ed15d8b0f6245fe030684501b083
diff --git a/libs/hwui/Properties.h b/libs/hwui/Properties.h
index eedc9e7..c4486a4 100644
--- a/libs/hwui/Properties.h
+++ b/libs/hwui/Properties.h
@@ -308,6 +308,7 @@
 
     static ProfileType getProfileType();
     static RenderPipelineType getRenderPipelineType();
+    static bool isSkiaEnabled();
 
     // Should be used only by test apps
     static bool waitForGpuCompletion;