* Modified tests to use tlogger.
* Fail on errors, with error expectations.
* Added expects and MixedCapsed grpclb_config tests
* Moved tlogger to grpctest, moved leakcheck tester to grpctest.go
* Added ExpectErrorN()
* Removed redundant leak checks
* Fixed new test
* Made tlogger globals into tlogger methods
* ErrorsLeft -> EndTest
* Removed some redundant lines
* Fixed error in test and empty map in EndTest
This PR moves the unbounded buffer implementation found in
`scStateUpdateBuffer` to the internal package. It also makes the buffer
work with `interface{}` type.
This addresses a TODO in the existing code. This will also help with the
eventual `BalancerManager` implementation which will supersede the
`ccBalancerWrapper` implementation found in balancer_conn_wrappers.go.
