Added method to get metadata out of the player.

Added a sample of the implementation that will
return if pause/forward/backward are supported
by the current stream.
diff --git a/android/playerdriver.cpp b/android/playerdriver.cpp
index 7ee216b..637d33f 100644
--- a/android/playerdriver.cpp
+++ b/android/playerdriver.cpp
@@ -25,6 +25,7 @@
 #include <media/thread_init.h>
 #include <utils/threads.h>
 #include <utils/List.h>
+#include <utils/SortedVector.h>
 #include <cutils/properties.h>
 #include <binder/Parcel.h>
 
@@ -1734,4 +1735,15 @@
     return INVALID_OPERATION;
 }
 
+
+// Called by the MediaPlayerService::Client to retrieve a set or all
+// the metadata (if request is empty).
+status_t PVPlayer::getMetadata(const SortedVector<MetadataType>& ids,
+                               Parcel *records) {
+    // FIXME: get the metadata about the stream. At this stage we are
+    // only interested about the liveness of the stream to
+    // enable/disable pause and seek in the UI.
+    return INVALID_OPERATION;
+}
+
 }; // namespace android