This adds an event that prints the total number of suites that will be
loaded, and includes the number of tests to be run in each group. This
enables a monotonic (if not entirely accurate) progress bar.

Closes #366

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1641353002 .

Closes #380

R=alexander.doroshko@gmail.com, kevmoo@google.com

Review URL: https://codereview.chromium.org//1637193003 .

Closes #279

R=lrn@google.com, kevmoo@google.com

Review URL: https://codereview.chromium.org//1604043003 .

See #385

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1636933002 .

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1594473002 .

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1578173003 .

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1578303003 .

Previously we were running the tearDown in parallel with the next test,
which caused some pretty bad bugs.

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1580243002 .

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1580973002 .

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1575223002 .

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1573223003 .

Closes #372

When the browser is paused at a breakpoint, the runner will now open a
command-line console with a "restart" command that will restart the
current test.

This currently has no tests, due to dart-lang/sdk#25369 and the lack of
a programmatic API for interacting with Observatory. I've tested it
reasonably thoroughly by hand, but it's more likely than the average
feature to have lurking bugs.

Closes #335

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1561073003 .

Support http_parser 2.0.0.

See dart-lang/http_multi_server#1.

This reverts commit 8833887b and
re-applies commit 71bfbdcd.

The original commit sometimes marked a controller as debugging or not
debugging after it had been closed. This fixes that bug.

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1496683003 .

This provides forward-compatibility for when we eventually add support
for full expressions when selecting tags.

See #16

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1491383003 .

In addition to looking slicker, this fixes a few issues with the old
implementation:

* Warnings are now printed as part of the corresponding load tests
  rather than just on standard out, meaning that they'll always be
  associated with the appropriate suite.

* Warnings are only printed once per suite, even if that suite is loaded
  on multiple platforms.

* Warnings are printed for tagged groups and suites themselves rather
  than for each test they contain.

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1490973003 .

See #16
See https://codereview.chromium.org/1405633004

I'm choosing not to add a section to the README until the feature is
complete. I don't want to encourage people to use tags for long-term
testing until we support a configuration that can include the set of
valid tags.

This makes a few behavioral changes to the original patch:

* Multiple values passed to --tags are interpreted as an intersection
  rather than a union (so --tags=a,b matches only tests tagged both "a"
  and "b").

* The @Tag annotation Now takes a mandatory argument that must be an
  Iterable<String>, rather than an optional argument that could be a
  String.

This adds missing Test.groupIDs and PrintEvent.testID fields, and adds a
description to clarify the purpose of FutureEvent. It also now verifies
that the protocol version is compatible.

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1487753003 .

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1475543002 .

This reverts commit 71bfbdcd. This
commit was causing intermittent stack overflows after running tests. I'm
reverting so we can get 0.12.6 out immediately; I'll re-apply once I
have time to fix the issues.

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1465403002 .

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1469863005 .

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1472883003 .

When a group was skipped, it was being filtered out entirely since it
had no tests. This preserves it so that it can print a skip message.

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1471963002 .

Closes #11

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1461293005 .