Use String instead of MethodDescriptor in ServerCallHandler.

Using MethodDescriptor before was abusive, but the alternative was not
clear.

The new gRPC protocol causes things to become more obvious. Headers,
method name, and timeout were the interesting things on the
MethodDescriptor. In the new protocol, headers are no longer going to be
treated differently from context. We are fine with passing the method
name. So that leaves just timeout, which we really will need more
methods for on the ServerCall object anyway.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=74889759
8 files changed
tree: bf8738d39d25e08283162fd2e02c942c4eb9f5e9
  1. auth/
  2. core/
  3. stub/
  4. testing/
  5. LICENSE