Fix an issue with duplicate reported analysis errors.

Fix an issue with duplicate reported analysis errors.

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

Committed: https://github.com/dart-lang/sdk/commit/eae2bf27470ff5c52c52647b27db224feb4f68d5

[devoncarew, 2017-04-02 18:51:35]

devoncarew@google.com changed reviewers:
+ brianwilkerson@google.com, danrubel@google.com

[devoncarew, 2017-04-02 18:51:36]

Fix an issue with duplicated reported analysis errors. This was introduced when
we did the work to speed up analysis on the chromium bots (~5.5x speedup, so we
want to keep that).

This CL separates out the machine more error reporter and the user facing error
reporter. The user facing one batches up issues as it hits them; the consumer of
the API is responsible for flushing the batched up errors. When flushing, the
reporter will de-dupe (and sort) the issues.

Longer term we want to reply on the context creation logic from the analysis
server. That will help us do things like assigning the right .packages file, and
properly respecting things like file excludes.

Fix #25697.

[Brian Wilkerson, 2017-04-03 14:03:50]

lgtm

[danrubel, 2017-04-03 15:32:04]

LGTM

https://codereview.chromium.org/2793813002/diff/1/pkg/analyzer_cli/lib/src/er...
File pkg/analyzer_cli/lib/src/error_formatter.dart (right):

https://codereview.chromium.org/2793813002/diff/1/pkg/analyzer_cli/lib/src/er...
pkg/analyzer_cli/lib/src/error_formatter.dart:221: List<CLIError> batchedErrors
= [];
Is there a reason to batch errors first and then dedupe them later? Would it be
more efficient to make this a Set so that errors are deduped as they are added
to this list?

[devoncarew, 2017-04-03 15:36:10]

https://codereview.chromium.org/2793813002/diff/1/pkg/analyzer_cli/lib/src/er...
File pkg/analyzer_cli/lib/src/error_formatter.dart (right):

https://codereview.chromium.org/2793813002/diff/1/pkg/analyzer_cli/lib/src/er...
pkg/analyzer_cli/lib/src/error_formatter.dart:221: List<CLIError> batchedErrors
= [];
On 2017/04/03 15:32:03, danrubel wrote:
> Is there a reason to batch errors first and then dedupe them later? Would it
be
> more efficient to make this a Set so that errors are deduped as they are added
> to this list?

Making it a Set would be better :) I'll do that.

[devoncarew, 2017-04-24 04:05:16]

Description was changed from

==========
Fix an issue with duplicate reported analysis errors.

BUG=
==========

to

==========
Fix an issue with duplicate reported analysis errors.

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

Committed:
https://github.com/dart-lang/sdk/commit/eae2bf27470ff5c52c52647b27db224feb4f68d5
==========

[devoncarew, 2017-04-24 04:05:17]

Committed patchset #5 (id:80001) manually as
eae2bf27470ff5c52c52647b27db224feb4f68d5 (presubmit successful).