Pre allocate client side strings per channel for method, scheme, path, and
authority.

For method and scheme, move these from channel to http_client_filter.
	Change on 2014/12/19 by klempner <klempner@google.com>
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=82536909
4 files changed