These changes should have been included in dc8c3239.

This is part of a change to ease internal usage of GRPC.

Previously, this alway generated a service file with a header.

However, this does not work well, it means whenver the ruby service plugin is
used, every proto file ends up with a service file.
	Change on 2015/01/07 by temiola <temiola@google.com>
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=83448951

	Change on 2015/01/06 by temiola <temiola@google.com>
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=83391912

	Change on 2014/12/10 by nnoble <nnoble@google.com>
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=81829127