Generate an error for active connections when the HTTP client is shutdown

Generate an error for active connections when the HTTP client is shutdown
    
Before the underlying sockets where just silently closed causing no more IO events on active connections no matter what state they where in.

Also added an optional "force" argument to HttpClient.shutdown. If that is false (the default) The HttpClient will not close active connections until they are done. This causes all pkg/http and pub tests to pass.
    
R=ager@google.com, nweiz@google.com
    
BUG=dart:6594
Committed: https://code.google.com/p/dart/source/detail?r=15275

[Søren Gjesse, 2012-11-21 13:34:52]

As the message says this causes some pkg/http and pub tests to fail due to the
way pkg/http uses the HttpClient.

I will try to extend this by having a "force" flag to HttpClient.shutdown.
Without force the HttpClient will be kept alive until all active connections are
done.

[Mads Ager (google), 2012-11-21 13:49:01]

LGTM

This also explains why pub hangs sometimes.

[nweiz, 2012-11-21 20:32:44]

On 2012/11/21 13:34:52, Søren Gjesse wrote:
> As the message says this causes some pkg/http and pub tests to fail due to the
> way pkg/http uses the HttpClient.
> 
> I will try to extend this by having a "force" flag to HttpClient.shutdown.
> Without force the HttpClient will be kept alive until all active connections
are
> done.

What's the behavior difference that's causing the pub and HTTP tests to fail?

[Mads Ager (google), 2012-11-22 07:24:22]

On 2012/11/21 20:32:44, nweiz wrote:
> On 2012/11/21 13:34:52, Søren Gjesse wrote:
> > As the message says this causes some pkg/http and pub tests to fail due to
the
> > way pkg/http uses the HttpClient.
> > 
> > I will try to extend this by having a "force" flag to HttpClient.shutdown.
> > Without force the HttpClient will be kept alive until all active connections
> are
> > done.
> 
> What's the behavior difference that's causing the pub and HTTP tests to fail?

That it is an error now to close an HttpClient prematurely before you have read
all data. The http library in pkg/http does that and pub does as well (through
the pkg/http library?). We should get that fixed ASAP since it could explain the
bug reports on pub occasionally hanging.

[Søren Gjesse, 2012-11-22 15:05:14]

PTAL

Added "force" flag to HttpClient.shutdown. See updated CL description. This
should fix pkg/http and pub tests where the HttpClient is shutdown while the
HTTP response handling might not be finished.

[Mads Ager (google), 2012-11-23 07:25:38]

LGTM

This is probably the right thing to do so that people can close the HttpClient
when they know they do not wnat to make more connections using it.

https://codereview.chromium.org/11411121/diff/10002/sdk/lib/io/http.dart
File sdk/lib/io/http.dart (right):

https://codereview.chromium.org/11411121/diff/10002/sdk/lib/io/http.dart#newc...
sdk/lib/io/http.dart:835: * resources. If [force] is [:false:] the
[:HttpClient:] will be
Could we add a comment to make it explicit what happens with connections that
are not done when you force a client shutdown?

[Søren Gjesse, 2012-11-23 09:08:47]

https://codereview.chromium.org/11411121/diff/10002/sdk/lib/io/http.dart
File sdk/lib/io/http.dart (right):

https://codereview.chromium.org/11411121/diff/10002/sdk/lib/io/http.dart#newc...
sdk/lib/io/http.dart:835: * resources. If [force] is [:false:] the
[:HttpClient:] will be
On 2012/11/23 07:25:38, Mads Ager wrote:
> Could we add a comment to make it explicit what happens with connections that
> are not done when you force a client shutdown?

It's already there, "If [force] is [:true:]..." above.

[Søren Gjesse, 2012-11-23 09:31:16]

https://codereview.chromium.org/11411121/diff/10002/sdk/lib/io/http.dart
File sdk/lib/io/http.dart (right):

https://codereview.chromium.org/11411121/diff/10002/sdk/lib/io/http.dart#newc...
sdk/lib/io/http.dart:835: * resources. If [force] is [:false:] the
[:HttpClient:] will be
On 2012/11/23 09:08:47, Søren Gjesse wrote:
> On 2012/11/23 07:25:38, Mads Ager wrote:
> > Could we add a comment to make it explicit what happens with connections
that
> > are not done when you force a client shutdown?
> 
> It's already there, "If [force] is [:true:]..." above.

Added more information on forced shutdown.