Encapsulate textures into their own Texture class

the main reason for doing this is so that we can have
access to informations about a texture (like its dimension)
close to where we generate and use shaders in ES 2.0.
Previously, there wasn't any way to get to a texture's size
from a RenderEngine implementation.

Bug: 8679321

Change-Id: I388b338a70d07e3e8177dde248710ea1e4c82dff
diff --git a/services/surfaceflinger/Android.mk b/services/surfaceflinger/Android.mk
index 7a14fb0..873bd5d 100644
--- a/services/surfaceflinger/Android.mk
+++ b/services/surfaceflinger/Android.mk
@@ -25,6 +25,7 @@
     RenderEngine/ProgramCache.cpp \
     RenderEngine/GLExtensions.cpp \
     RenderEngine/RenderEngine.cpp \
+    RenderEngine/Texture.cpp \
     RenderEngine/GLES10RenderEngine.cpp \
     RenderEngine/GLES11RenderEngine.cpp \
     RenderEngine/GLES20RenderEngine.cpp