* enable lint unnecessary_new

* fix tests

* fix tests

* fix tests

* Fixes resulting from audit of issues links

I looked at every link to GitHub in our repo. For cases where we had a TODO that was waiting for a bug to be fixed, and the bug has now been fixed, I applied the pending change. For cases where the link was out of date, I updated the link.

* Update run_test.dart

skip this test again since it failed on linux and macos bots

It was causing problems rolling Flutter into Fuchsia

* re-enable lint unnecessary_const

* remove trailling whitespaces

* remove unnecessary const (after merge)

This reverts commit cc1cf13e.

* Remove the 'app' domain from flutter daemon

By default the daemon won't register the "app" domain, you need to opt-in (which the 'run' command does, as well as the tests for the app functionality).

Fixes #6658.

* Tweak text

* Put restart/callServiceExtension/stop back into daemon mode

* Add a comment about removing discoverApps

This is an attempt to reland #18488 with less breakage on macOS.

This reverts commit 77508722.

* add device.supportsHardwareRendering and display a message if true

* Address some comments

https://github.com/flutter/flutter/issues/14519

* route device issue diagnostics to flutter doctor

* review comments

* review comments

This allows `flutter run` to work on hosts that are IPv6-only.

I got tired of drive-by spelling fixes, so I figured I'd just take care of them all at once.

This only corrects errors in the dartdocs, not regular comments, and I skipped any sample code in the dartdocs. It doesn't touch any identifiers in the dartdocs either. No code changes, just comments.

* Add --trace-skia parameter to flutter run

Skia tracing is extremely useful for internal debug, but reduces the
amount of space available in the Dart Timeline buffers.
Disable skia tracing by default and expose them via the --trace-skia
flag.

* Roll Engine to 57a1445a45964d386500c39f5e8d06db060abadb

This adds --preview-dart-2 flag that enables use of Dart 2.0 Frontend in Flutter tools.

This reverts commit 8d07d3f6.

* perform the initial poll for devices quicker

* add a Poller class

* test the new Poller class

Apply a 30 second timeout to Android/iOS device polling.

If there's a device poll already in progress, skip polling for new
devices; wait for the first request to return/timeout.

* Guess sign with the first certificate when multiple are available in machine mode

* review

This reverts commit b2909a24.

This resubmits the following patches:

1. Use Xcode instruments to list devices (#10801)
Eliminates the dependency on idevice_id from libimobiledevice. Instead,
uses Xcode built-in functionality.

2. Make device discovery asynchronous (#10803)
Migrates DeviceDiscovery.devices and all device-specific lookup to be
asynchronous.

* Revert "Make device discovery asynchronous (#10803)"
This reverts commit 972be9c8.

* Revert "Use Xcode instruments to list devices (#10801)"
This reverts commit 37bb5f13.

This is to resolve a failure that looks related to a bad install of Xcode 8.0
on our build bots and should be reinstated when the infra issue is diagnosed
and resolved.

Instruments worked well when this was originally landed, and on the
following commit, but started failing two commits after this originally
landed. Manual invocation of instruments on the build host currently
results in:

```
dyld: Library not loaded: @rpath/InstrumentsAnalysisCore.framework/Versions/A/InstrumentsAnalysisCore
  Referenced from: /Applications/Xcode8.0.app/Contents/Developer/usr/bin/instruments
  Reason: image not found
Abort trap: 6
```

It appears the /Applications/Xcode8.0.app/Contents/Applications
directory (which contains Instruments) is missing on the host.

Migrates DeviceDiscovery.devices and all device-specific lookup to be
asynchronous.

This message will be picked up by IntelliJ and shown to the user in a toast.

If the user specified a non-exact device id, it was producing
an exception whereby we were trying to listen to the
`getAllConnectedDevies()` stream twice.