Fix instance of using mPackages as the lock

It looks like the day that the switch to mLock went in, another change
merged in that added code that included synchronization on mPackages.
This gets us back to only using mLock.

Test: Builds
Bug: N/A
Change-Id: I6c9332a135efd4f0189ed6f27f43ba51f025cf8f
1 file changed