as a debug option SrufaceFlinger can now connect to DDMS

this is disabled by default. To enable:
  setprop debug.sf.ddms 1

this debug option requires to restart SurfaceFlinger

Change-Id: Ic2f8050b29911b55bcd21721648b6978700c277d
diff --git a/services/surfaceflinger/SurfaceFlinger.h b/services/surfaceflinger/SurfaceFlinger.h
index 6f93f5b..89df0de 100644
--- a/services/surfaceflinger/SurfaceFlinger.h
+++ b/services/surfaceflinger/SurfaceFlinger.h
@@ -371,6 +371,7 @@
                 // don't use a lock for these, we don't care
                 int                         mDebugRegion;
                 int                         mDebugBackground;
+                int                         mDebugDDMS;
                 int                         mDebugDisableHWC;
                 volatile nsecs_t            mDebugInSwapBuffers;
                 nsecs_t                     mLastSwapBufferTime;