Fixing FBO font rendering bug that resulted from using old surface size.

Change-Id: I31d0967bb36ca6ffb6a4c8194597d3c523cfe954
diff --git a/libs/rs/rsContext.h b/libs/rs/rsContext.h
index 199cc5a..c6582c9 100644
--- a/libs/rs/rsContext.h
+++ b/libs/rs/rsContext.h
@@ -164,6 +164,9 @@
     uint32_t getWidth() const {return mWidth;}
     uint32_t getHeight() const {return mHeight;}
 
+    uint32_t getCurrentSurfaceWidth() const;
+    uint32_t getCurrentSurfaceHeight() const;
+
     mutable ThreadIO mIO;
 
     // Timers