Revert "Revert "fix [2793164] Spam 2x/second with TOT master in SurfaceFlinger""

This reverts commit 330dd304a471d260a73e342a240921c03c825f99.
diff --git a/libs/surfaceflinger/Layer.h b/libs/surfaceflinger/Layer.h
index dcb27a0..e1d283b 100644
--- a/libs/surfaceflinger/Layer.h
+++ b/libs/surfaceflinger/Layer.h
@@ -37,9 +37,10 @@
 
 // ---------------------------------------------------------------------------
 
-class Client;
-class UserClient;
 class FreezeLock;
+class Client;
+class GLExtensions;
+class UserClient;
 
 // ---------------------------------------------------------------------------
 
@@ -206,6 +207,7 @@
     // constants
     sp<Surface> mSurface;
     PixelFormat mFormat;
+    const GLExtensions& mGLExtensions;
     bool mNeedsBlending;
     bool mNeedsDithering;