Fix for bug 4371230.
- Generate unique ID for each DrmManagerClient in native side
- Fix the bug where multiple clients could use the same ID
- Return the correct unique ID back to Java
- Add a flag in the unique ID to separate native client and Java client

Change-Id: Ia4574b6b0a526f2335a65380975dc62f9a6e7f9b
12 files changed