This argument will enable mocking of os-layer process invocations,
where the mock behavior will come from replaying a previously-
recorded set of invocations. At the point of process invocation,
the key metadata for the invocation will be looked up in the
recording's manifest, and iff a matching record exists in the
manifest, the process will be mocked out with data derived from
the corresponding recorded process (e.g. stdout, stderr, exit code).

* Add --record-to option to flutter tools

This option will cause flutter tools to record all process
invocations that occur and serialize their stdout and stderr
to files that get added to a "recording" ZIP file. This is
part of an effort to be able to test flutter tools in a hermetic
environment.

As a side-benefit, this recording should prove an excellent
attachment to any bug report.

* Remove the workaround that pinned args to v0.13.6
This reverts most of the changes in commit 6331b6c8
* throw exception if exit code is not an integer
* rework command infrastructure to throw ToolExit when non-zero exitCode
* convert commands to return Future<Null>
* cleanup remaining commands to use throwToolExit for non-zero exit code
* remove isUnusual exception message
* add type annotations for updated args package

* convert pubGet to throw ToolExit on non-zero exit code
* convert commandValidator to throw ToolExit for non-zero exit code
* convert flutter commands to throw ToolExit for non-zero exit code
* use convenience method throwToolExit
* only show "if this problem persists" for unusual exceptions

Fixes #6417

With the old policy the most recent log would not be printed until the next
log is produced (which may be indefinitely).  This change prints logs
immediately along with a time delta since the previous log.

When using --use-application-binary:

- [x] Stop flutter run from checking for a pubspec.yaml in current directory
- [x] Stop flutter run from invoking pub get
- [x] Set 'shouldBuild' based on --use-application-binary
- [x] Stop requiring 'lib/main.dart' to be present before running.
- [x] Stop building an FLX when launching on Android

* show hidden flags when showing verbose help
* flutter -v show verbose help

* refactor _run to runCmd

* replace requiresProjectRoot getter with call to commandValidator

* replace requiresDevice getter with call to findTargetDevice

* trace command requires a debug connection, not a device

* inline androidOnly getter

* rename command methods to verifyTheRunCmd and runCmd

* move common verification into BuildSubCommand

* rename deviceForCommand to device

* rename methods to verifyThenRunCommand and runCommand

When flutter run is used on a Mac and no devices are specified or attached, suggest launching a simulator first. Fixes https://github.com/flutter/flutter/issues/5674

* improve device matching error message
fixes https://github.com/flutter/flutter/issues/5675

Do not throw when resolving a local engine if the .packages map does not include the flutter package (#5519)

* update the cache earlier

* add documentation

* make flutter run work with a pre-built apk

* refactor to remove the buildDir param

* This reverts commit 5e7e7b6e.

* default to lib/main.dart

This reverts commit 32ad81c8.

It can cause trouble if the user has a newer Android SDK installed normally.
Instead, just use the normal Android SDK.

* Fix `flutter upgrade`

* Fix builds on iOS

This prevents multiple simultaneous runs of the analyzer from stomping
over each other (e.g. multiple runs of 'update-packages'). Certain
long-lived commands (like analyze, run, logs) are exempted once they've
done enough work to be safe from most stomping action.

This still doesn't make us entirely safe from craziness, e.g. if you're
half way through an 'update-packages' run and you call 'git pull', who
knows what state you'll end up in. But there's only so much one can do.

Fixes https://github.com/flutter/flutter/issues/2762

Also, make it clear the screen between results so it's more obvious
what's going on when you have new results (especially when you have
fixed everything).

* refactor the --resident run option into a separate file

* update daemon to run --resident apps

* re-plumbing daemon start

* send app logs

* update tests

* review changes

* fix test runner

* remove PackageMap.createGlobalInstance; rely on the ctor

* review comments

* resolve symlinks in paths to flutter

* review comments

This reverts commit 8f69cccc.

* dissallow -release mode on emulators

* have the help text print the default mode

This passes the information through Xcode to the `flutter build aot` call via
the environment so that it picks up the right artifacts.

Fixes #4186

* rebuild when the build type changes

* handle local engine builds

* also check the timestamp

* allow per-command analytics suppression

* rev the usage package dep

Artifacts from local engine builds will be found based on the --local-engine flag