Tessellate on worker threads

Tessellate and cache (where possible) shadow and round rect
tessellation tasks.

Change-Id: I2cfda8e11d83d51ea74af871235cf26e8f831d40
diff --git a/libs/hwui/Android.mk b/libs/hwui/Android.mk
index 442f327..900a72e 100644
--- a/libs/hwui/Android.mk
+++ b/libs/hwui/Android.mk
@@ -51,6 +51,7 @@
 		SpotShadow.cpp \
 		StatefulBaseRenderer.cpp \
 		Stencil.cpp \
+		TessellationCache.cpp \
 		Texture.cpp \
 		TextureCache.cpp \
 		TextDropShadowCache.cpp