Use write instead of writeln for client/server communication.

Use write instead of writeln for client/server communication.

We have observed that each string sent from the server to the client
using stdout.write() takes at least one cycle of the event loop to
complete.  Since writeln() is implemented using two calls to write(),
this means that streaming of messages to the client was almost always
falling behind the actual rate of analysis, resulting in very annoying
delays for the user.

As a stopgap, send each message from server to client using a single
call to write().  This doesn't completely solve the problem, but it
should reduce its impact while we work on a better solution.

R=scheglov@google.com

Committed: https://code.google.com/p/dart/source/detail?r=41959

[Paul Berry, 2014-11-25 14:03:05]

paulberry@google.com changed reviewers:
+ scheglov@google.com

[scheglov, 2014-11-25 15:08:33]

LGTM

[Paul Berry, 2014-11-25 16:06:35]

Committed patchset #1 (id:1) manually as 41959 (presubmit successful).