Split off a Driver class from analysis server's HttpAnalysisServer.

Split off a Driver class from analysis server's HttpAnalysisServer.

The Driver class sits above the HttpAnalysisServer, parsing command
line options and deciding how the sever should be run.  With this
change, HttpAnalysisServer now contains only http-specific code.

R=brianwilkerson@google.com, jwren@google.com

Committed: https://code.google.com/p/dart/source/detail?r=35075

[Paul Berry, 2014-04-15 18:03:00]

Note: http_server.dart probably belongs in lib/src/ now, since it's no longer
used by bin/server.dart so it shouldn't be considered public.  I'd like to
postpone that change until a later CL so we can see how the rest of the
stdio-based server shakes out.

[Brian Wilkerson, 2014-04-15 18:16:29]

LGTM

https://codereview.chromium.org/239573002/diff/1/pkg/analysis_server/lib/http...
File pkg/analysis_server/lib/http_server.dart (right):

https://codereview.chromium.org/239573002/diff/1/pkg/analysis_server/lib/http...
pkg/analysis_server/lib/http_server.dart:33: HttpAnalysisServer(SocketServer
this.socketServer);
nit: The standard practice is to not include a type annotation with a field
formal parameter.

[jwren, 2014-04-15 18:17:15]

LGTM

[Paul Berry, 2014-04-15 19:55:30]

Committed patchset #1 manually as r35075 (presubmit successful).