This switches pub's tests over to using the stream matchers built into
test, as well as the test_descriptor, test_process, and
shelf_test_handler packages. It uses async/await rather than
scheduled_test's task queue.

This removes a layer of indirection which should make it much easier to
work on pub's test infrastructure, especially for people unfamiliar with
scheduled_test.

R=rnystrom@google.com

Review URL: https://codereview.chromium.org//1585513002 .

R=rnystrom@google.com

Review URL: https://codereview.chromium.org//1215833002.

R=rnystrom@google.com

Review URL: https://codereview.chromium.org//1153643002

This uses the source spans exposed by the yaml package to associate pubspec
errors visually with the section of the pubspec that caused them.

R=rnystrom@google.com
BUG=14999

Review URL: https://codereview.chromium.org//351703004

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@37675 260f80e4-7a28-3924-810f-c04153c831b5

BUG=https://code.google.com/p/dart/issues/detail?id=7351
R=nweiz@google.com

Review URL: https://codereview.chromium.org//26284002

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@28330 260f80e4-7a28-3924-810f-c04153c831b5

The user-visible effect of this is to make operations that only look at part of
a pubspec work if other parts of the pubspec are somehow invalid. This is
particularly important for the following scenario:

1. We release a version of pub in SDK 1.0.0 that parses pubspec field "foo" as
   an integer.

2. Sally uploads version 0.1.0 of her package, libsally.

3. We release a new version of pub in SDK 1.1.0 that supports strings in "foo".

4. Sally uploads libsally 0.2.0, which uses a string in "foo". The new version
   of libsally has an SDK constraint of ">= 1.1.0", since it uses the new "foo"
   feature.

5. Tom is using SDK 1.0.0 and runs "pub install" in a package that depends on
   libsally.

Everyone's done everything right here; we made a backwards-compatible pubspec
change, Sally chose the correct SDK constraint, and Tom has a dependency on a
package that has a compatible version available.

However, prior to this change, Tom's "pub install" would crash. His outdated
version of pub would try and fail to parse libsally 0.2.0's "foo" field, and his
version resolution would crash. With this change, it will only attempt to parse
the SDK constraint portion of Sally's pubspec, and ignore anything else it
doesn't understand.

R=rnystrom@google.com
BUG=

Review URL: https://codereview.chromium.org//24246002

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@27784 260f80e4-7a28-3924-810f-c04153c831b5

BUG=
R=nweiz@google.com

Review URL: https://codereview.chromium.org//22941002

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@26040 260f80e4-7a28-3924-810f-c04153c831b5

Now that hosted deps in tests can be just like they are in normal
pubspecs since the server URL is in an env var, we can simplify
the tests.

R=nweiz@google.com

Review URL: https://codereview.chromium.org//19592015

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@25305 260f80e4-7a28-3924-810f-c04153c831b5

Review URL: https://codereview.chromium.org//16034002

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@23182 260f80e4-7a28-3924-810f-c04153c831b5

BUG=http://dartbug.com/9697

Review URL: https://codereview.chromium.org//13839023

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@21237 260f80e4-7a28-3924-810f-c04153c831b5

This was originally committed as r20250. Due to issue 9294, this failed on
Windows. This commit works around that issue.

BUG=8511

Review URL: https://codereview.chromium.org//12437022

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@20264 260f80e4-7a28-3924-810f-c04153c831b5

This reverts r20250, which was failing on Windows.

BUG=8511

Review URL: https://codereview.chromium.org//12782005

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@20253 260f80e4-7a28-3924-810f-c04153c831b5

BUG=8511

Review URL: https://codereview.chromium.org//12794007

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@20250 260f80e4-7a28-3924-810f-c04153c831b5

Review URL: https://codereview.chromium.org//11943005

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@17300 260f80e4-7a28-3924-810f-c04153c831b5

Another take of https://codereview.chromium.org/11410033/ with status changes applied for co19 tests.

BUG=

Review URL: https://codereview.chromium.org//11369210

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@14837 260f80e4-7a28-3924-810f-c04153c831b5

BUG=

Review URL: https://codereview.chromium.org//11312203

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@14833 260f80e4-7a28-3924-810f-c04153c831b5

BUG=

Review URL: https://codereview.chromium.org//11410033

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@14829 260f80e4-7a28-3924-810f-c04153c831b5

This means all imports of unittest in our test code had to change to include 'lib' in the path.
While doing that change I changed the library/imports to the new syntax in the affected files.
Review URL: https://codereview.chromium.org//11301046

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@14443 260f80e4-7a28-3924-810f-c04153c831b5

Review URL: https://codereview.chromium.org//11093012

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@13391 260f80e4-7a28-3924-810f-c04153c831b5

Windows is slow and our large tests suites time out.

Review URL: https://codereview.chromium.org//11035066

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge@13315 260f80e4-7a28-3924-810f-c04153c831b5