Make test iframes visible when debugging.

Closes #429

Closes #485

R=nweiz@google.com
BUG=

Review URL: https://codereview.chromium.org//2392743005 .

Don't capture stack traces by default.

Stack traces are now only captured for the JSON reporter. Capturing
traces was slow enough to be a serious problem for test suites with many
tests.

Closes #457

Closes #461

Closes #453

R=devoncarew@google.com

Review URL: https://codereview.chromium.org//2271383002 .

This isn't used by test proper, but it's needed by some
Google-internal code.

R=jmesserly@google.com

Review URL: https://codereview.chromium.org//2269403002 .

Updates `test` to be constraint-compatible with the latest analyzer (0.28.0-alpha.1).

BUG=
R=brianwilkerson@google.com, nweiz@google.com

Review URL: https://codereview.chromium.org//2255083003 .

Closes #327

R=leafp@google.com

Review URL: https://codereview.chromium.org//2184543002 .

BUG=https://github.com/dart-lang/test/issues/442
R=kevmoo@google.com

Review URL: https://codereview.chromium.org//2124983005 .

Closes #393

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//2099553002 .

Closes #394

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//2123353002 .

The new constraint reflects the actual APIs we're using.

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//2087003004 .

Closes #420

Review URL: https://codereview.chromium.org//2066113002 .

This version hasn't been released yet.

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

Review URL: https://codereview.chromium.org//2048773002 .

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//2039413002 .

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//2012113002 .

This prepares for https://codereview.chromium.org/1994743003/, which
moves some of these functions into the collection package. Once that
lands, we'll add a follow-up CL to use those APIs from collection.

R=jakemac@google.com

Review URL: https://codereview.chromium.org//1991303002 .

We weren't notifying the controller when all the live tests had been
added to the suite.

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1981283006 .

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1960503002 .

R=rnystrom@google.com, jmesserly@google.com

Review URL: https://codereview.chromium.org//1921913004 .

Looks like we hadn't run the analyzer against all the top-level
libraries.

See dart-lang/matcher@400e87928fdceeee883c95c8a81e96fdacfdc399

Closes #63

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1829483002 .

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1801363007 .

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1797113002 .

This also adds the ability to pass --name or --plain-name multiple times
on the command line.

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1802133002 .

Closes #83

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1782473005 .

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1756523003 .

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1731483002 .

The --tags and --exclude-tags flags now support boolean selector syntax,
as do the keys in the "tags" configuration field.

Closes #16

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1715583003 .

See #16

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1691173002 .

Closes #396

R=rnystrom@google.com

Review URL: https://codereview.chromium.org//1684063004 .

This will ensure that the latest version of test that claims to support
args 0.12.0 will actually run correctly with that version. After this is
released, I'll re-add the separators and fix the args constraint.

See #396

R=rnystrom@google.com

Review URL: https://codereview.chromium.org//1683923005 .

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1673493002 .

R=kevmoo@google.com

Review URL: https://codereview.chromium.org//1659023003 .