Bug fixes of DRM framework.

- Add death listener to clean-up drmserver appropriately
  when drmserver died.
- Remove "static" declaration of mUniqueIdVector because it was not
  needed to be static variable.
- Remove "class DrmContentIds;" because the class does not exist.
- contentPath in saveRights() could be empty because
  it is not required by some DRM schemes.
- Fix naming convention to use sXXX for static variables.
- Fix typo

Change-Id: I7d440488fc074c200f1009d1bafafeffebd690b2
diff --git a/drm/libdrmframework/include/DrmManagerClientImpl.h b/drm/libdrmframework/include/DrmManagerClientImpl.h
index 0cba8d4..564896b 100644
--- a/drm/libdrmframework/include/DrmManagerClientImpl.h
+++ b/drm/libdrmframework/include/DrmManagerClientImpl.h
@@ -407,9 +407,17 @@
     Mutex mLock;
     sp<DrmManagerClient::OnInfoListener> mOnInfoListener;
 
+    class DeathNotifier: public IBinder::DeathRecipient {
+        public:
+            DeathNotifier() {}
+            virtual ~DeathNotifier();
+            virtual void binderDied(const wp<IBinder>& who);
+    };
+
 private:
-    static Mutex mMutex;
-    static sp<IDrmManagerService> mDrmManagerService;
+    static Mutex sMutex;
+    static sp<DeathNotifier> sDeathNotifier;
+    static sp<IDrmManagerService> sDrmManagerService;
     static const sp<IDrmManagerService>& getDrmManagerService();
     static const String8 EMPTY_STRING;
 };