stagefright: metadata retriever changes for capture fps

bug: 19460202
Change-Id: I20afded0b7eec45b2f25b51cf59d9f48eada74d8
diff --git a/include/media/mediametadataretriever.h b/include/media/mediametadataretriever.h
index b35cf32..7191965 100644
--- a/include/media/mediametadataretriever.h
+++ b/include/media/mediametadataretriever.h
@@ -57,6 +57,7 @@
     METADATA_KEY_IS_DRM          = 22,
     METADATA_KEY_LOCATION        = 23,
     METADATA_KEY_VIDEO_ROTATION  = 24,
+    METADATA_KEY_CAPTURE_FRAMERATE = 25,
 
     // Add more here...
 };