This reverts commit 202c1b42.

We were using the `defaults` command-line utility to parse
Plist files, but it was never supported by Apple, and it
appears that in an upcoming OS release, it will be less likely
to work:

> WARNING: The defaults command will be changed in an upcoming
> major release to only operate on preferences domains. General
> plist manipulation utilities will be folded into a different
> command-line program.

Fixes https://github.com/flutter/flutter/issues/37701

Android now exclusively uses ELF shared libraries, and
iOS uses assembly.

add ignorable track-widget-creation flag to build  and remove --track-widget-creation from xcode backend aot build aot (#31399)

Reland: Ensure that flutter run/drive/test/update_packages only downloads required artifacts  (#30254)

This flag makes flutter build aot report timings for substeps (e.g.
frontend compilation and gen_snapshot) in a machine readable form.

Revert "Ensure that flutter run/drive/test/update_packages only downloads required artifacts (#30075)" (#30232)

* 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

This reverts commit dd65a546.

These are essentially self-inflicted race conditions. Instead of timeouts we're going to try a more verbose logging mechanism that points out when things are taking a long time.

This reverts commit 76f70810.

* Remove many timeouts.

These are essentially self-inflicted race conditions. Instead of timeouts we're going to try a more verbose logging mechanism that points out when things are taking a long time.

* Get the attach tests to pass.

* Apply review comments from Todd

* More review comment fixes

* Put back the extended timeouts here now that I know why we have them...

Ensure that cached dill files for builds with --track-widget-creation
always have .track. in the file name to avoid mixing transformed and
untransformed kernel files.

Also includes
  * Updates to affected tests
  * Change flutter_tools to pass package URIs to the Dart front end
    instead of filesystem paths

* enable lint unnecessary_new

* fix tests

* fix tests

* fix tests

Fixes https://github.com/flutter/flutter/issues/21215

This patch eliminates the --preview-dart-2/--no-preview-dart-2 flag,
hardcoding all uses to true. It also defaults all previewDart2 method
parameters to true, where they hadn't yet been.

A series of subsequent patches will eliminate all previewDart2
parameters and the associated code from within the codebase.

Disallow calling stop() or cancel() multiple times. This means that
when you use startProgress you have to more carefully think about what
exactly is going on.

Properly cancel startProgress in non-ANSI situations, so that
back-to-back startProgress calls all render to the console.

This reverts commit 0636c6fe.