Add a way to query GL extensions.

Change-Id: Ic27dbf72289dacf641b640a749fbd40c12cd474f
diff --git a/libs/hwui/OpenGLRenderer.h b/libs/hwui/OpenGLRenderer.h
index b82366b..6d30282 100644
--- a/libs/hwui/OpenGLRenderer.h
+++ b/libs/hwui/OpenGLRenderer.h
@@ -40,6 +40,7 @@
 #include "PatchCache.h"
 #include "Vertex.h"
 #include "FontRenderer.h"
+#include "Extensions.h"
 
 namespace android {
 namespace uirenderer {
@@ -369,6 +370,8 @@
     LayerCache mLayerCache;
     GradientCache mGradientCache;
     PatchCache mPatchCache;
+
+    Extensions mExtensions;
 }; // class OpenGLRenderer
 
 }; // namespace uirenderer