Make alarm initialization take a timespec now.

This will allow combining of gpr_now() calls, and make it easier to test the
alarm code in the future.
	Change on 2014/12/16 by ctiller <ctiller@google.com>
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=82246768
5 files changed