Use the context_priority extension when present.

Change-Id: I12eadf1e32d576de5d811fba44afa73263e13eef
diff --git a/services/surfaceflinger/Android.mk b/services/surfaceflinger/Android.mk
index a14bfb5..e2f8a74 100644
--- a/services/surfaceflinger/Android.mk
+++ b/services/surfaceflinger/Android.mk
@@ -23,6 +23,10 @@
 ifeq ($(TARGET_BOARD_PLATFORM), omap3)
 	LOCAL_CFLAGS += -DNO_RGBX_8888
 endif
+ifeq ($(TARGET_BOARD_PLATFORM), s5pc110)
+	LOCAL_CFLAGS += -DHAS_CONTEXT_PRIORITY
+endif
+
 
 # need "-lrt" on Linux simulator to pick up clock_gettime
 ifeq ($(TARGET_SIMULATOR),true)
diff --git a/services/surfaceflinger/DisplayHardware/DisplayHardware.cpp b/services/surfaceflinger/DisplayHardware/DisplayHardware.cpp
index 0515110..28a512e 100644
--- a/services/surfaceflinger/DisplayHardware/DisplayHardware.cpp
+++ b/services/surfaceflinger/DisplayHardware/DisplayHardware.cpp
@@ -199,8 +199,18 @@
      * Create our OpenGL ES context
      */
     
-    context = eglCreateContext(display, config, NULL, NULL);
-    
+
+    EGLint contextAttributes[] = {
+#ifdef EGL_IMG_context_priority
+#ifdef HAS_CONTEXT_PRIORITY
+#warning "using EGL_IMG_context_priority"
+        EGL_CONTEXT_PRIORITY_LEVEL_IMG, EGL_CONTEXT_PRIORITY_HIGH_IMG,
+#endif
+#endif
+        EGL_NONE, EGL_NONE
+    };
+    context = eglCreateContext(display, config, NULL, contextAttributes);
+
     mDisplay = display;
     mConfig  = config;
     mSurface = surface;