Enable clang for libui/libgui/surfaceflinger

Enables clang and C++11 for libui/libgui/surfaceflinger, and
eliminates all compile-time warnings.

Change-Id: Ie237fdb5ae44f2bfcddaa884f9c65ec3f08ae50f
diff --git a/include/ui/FramebufferNativeWindow.h b/include/ui/FramebufferNativeWindow.h
index 5cd8101..6b66d5f 100644
--- a/include/ui/FramebufferNativeWindow.h
+++ b/include/ui/FramebufferNativeWindow.h
@@ -14,11 +14,13 @@
  * limitations under the License.
  */
 
+#ifndef INCLUDED_FROM_FRAMEBUFFER_NATIVE_WINDOW_CPP
+#warning "FramebufferNativeWindow is deprecated"
+#endif
+
 #ifndef ANDROID_FRAMEBUFFER_NATIVE_WINDOW_H
 #define ANDROID_FRAMEBUFFER_NATIVE_WINDOW_H
 
-#warning "FramebufferNativeWindow is deprecated"
-
 #include <stdint.h>
 #include <sys/types.h>