The testing rule MockFlagsRule is not a "Mock". Rename the class name.
Bug: 280833463
Test: presubmit
Change-Id: I644537163e07dcf55cd69af3690e435251149349
Add usage of test mode of java_aconfig_library.
Add local host unit test of contentlibs
Test: atest ContentLibs_test_host --host
Bug: 287644619
Change-Id: Ib99a3f2b692d3251d445a2e188325ee0b0b6b268