diff --git a/include/gui/SurfaceTexture.h b/include/gui/SurfaceTexture.h
index d7dd4d6..27d863d 100644
--- a/include/gui/SurfaceTexture.h
+++ b/include/gui/SurfaceTexture.h
@@ -271,7 +271,8 @@
               mRequestBufferCalled(false),
               mTransform(0),
               mScalingMode(NATIVE_WINDOW_SCALING_MODE_FREEZE),
-              mTimestamp(0) {
+              mTimestamp(0),
+              mFrameNumber(0) {
             mCrop.makeInvalid();
         }
 
@@ -340,6 +341,10 @@
         // mTimestamp is the current timestamp for this buffer slot. This gets
         // to set by queueBuffer each time this slot is queued.
         int64_t mTimestamp;
+
+        // mFrameNumber is the number of the queued frame for this slot.
+        uint64_t mFrameNumber;
+
     };
 
     // mSlots is the array of buffer slots that must be mirrored on the client
@@ -476,6 +481,12 @@
     // around a GL driver limitation on the number of FBO attachments, which the
     // browser's tile cache exceeds.
     const GLenum mTexTarget;
+
+    // mFrameCounter is the free running counter, incremented for every buffer queued
+    // with the surface Texture.
+    uint64_t mFrameCounter;
+
+
 };
 
 // ----------------------------------------------------------------------------