[ Merge of http://go/wvgerrit/143909 ]
The max. number of DRM keys that can be loaded depends on the resource
rating.
Add a test to verify:
1. We can load up to MAX. drm keys
2. Loading the MAX+1 key can fail
3. The loaded keys should work even if loading other keys failed
Bug: 209084113
Test: opk_ta, run_x86_64_tests, run_level3_static_tests,
run_fake_l1_tests
Test: GtsMediaTestCases on sunfish
Change-Id: Ib9821e8a1994d41d3e9c2063440c109a2332ba89
57353b4941