This is a partial re-application of #24669, which was
reverted due to Fuchsia breakages.

https://github.com/flutter/flutter/issues/24413

* add trailing commas on list/map/parameters

* add trailing commas on Invocation with nb of arg>1

* add commas for widget containing widgets

* add trailing commas if instantiation contains trailing comma

* revert bad change

Fixes https://github.com/flutter/flutter/issues/24413

* enable lint unnecessary_new

* fix tests

* fix tests

* fix tests

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.

ProcessResult.stdout has static type dynamic so for
inference to infer proper type argument for the map
invocation we need to cast stdout to String explicitly.

Fixes #17163

This updates AppContext per the recommendations in #15352

Fixes #15352

* Revert "Revert "Make artifact downloading more robust for flaky networks" (#13995)"

This reverts commit 33d8a035.

* Use subdirectories to organize cached files

* Fix unauthorized import

* Revert "Change github readme links to be served by github (#13929)"

This reverts commit fd516d95.

* Revert " Rename SemanticsFlags to SemanticsFlag (#13994)"

This reverts commit 24e3f705.

* Revert "Make artifact downloading more robust for flaky networks (#13984)"

This reverts commit 4d37e03e.

* First version

* Add a clarifying comment

* Add verify to ZipDecoder.decodeBytes call

* Review comments

* Need OS Error for missing files

* FileSystemException, not OSError.

Add a flutter doctor --android-licenses command that locates and runs the Android SDK license manager (#9892)

See https://github.com/flutter/flutter/issues/8438

The old `whichAll` implementation was not considering different extensions for executables on Windows. By defering to OS-built-in tools we avoid implementing it.

Fixes #8882.

1. Add `PortScanner` abstraction so that we don't do actual port scanning
   in tests.
2. Don't change the real `cwd` of the isolate during tests, as it affects
   all tests, not just the current running test.

Fixes #8761

Fixes #8618

This adds support for a `--bug-report` flag, which is a recording
that:
  - includes the arguments that were passed to the command runner
  - is zipped up for easy attachment in Guthub issues