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/DrmManager.h b/drm/libdrmframework/include/DrmManager.h
index e05366d..86a5ff4 100644
--- a/drm/libdrmframework/include/DrmManager.h
+++ b/drm/libdrmframework/include/DrmManager.h
@@ -30,7 +30,6 @@
 class DrmRegistrationInfo;
 class DrmUnregistrationInfo;
 class DrmRightsAcquisitionInfo;
-class DrmContentIds;
 class DrmConstraints;
 class DrmMetadata;
 class DrmRights;
@@ -141,7 +140,7 @@
     bool canHandle(int uniqueId, const String8& path);
 
 private:
-    static Vector<int> mUniqueIdVector;
+    Vector<int> mUniqueIdVector;
     static const String8 EMPTY_STRING;
 
     int mDecryptSessionId;