* have flutter run --machine log to stdout

* add a test

* add docs; fix type annotation lint

* 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

- [x] Remove old benchmark code from the non-hot runner.
- [x] Remove some dead code.
- [x] Fix a throw that should be a rethrow.

* add flutter run --machine flag
* refactor daemon stdin/out command stream/response
* extract daemon startApp method
* refactor flutter run --machine to call daemon.startApp

* Fix Missing newline in flutter run help
Issue #6461

* Fix overtab from multiline

Issue #6461

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

* make flutter run work with a pre-built apk

* refactor to remove the buildDir param

* support hot mode from the daemon protocol

* move method params to constructor

* General improvoments to the loader app:
   * Show a message after 8 seconds if no connection comes in.
   * Show a progress bar as files are being uploaded.
   * Hide the spinner just before launching the application.

* General improvements to the "flutter run" UI:
   * Add "?" key as a silent alias for "h".
   * Make the help text bold so it doesn't get mixed with the logs.
   * Make "R" do a cold restart when hot reload is enabled.

* Supporting features and bug fixes:
   * Add support for string service extensions.

* Other bug fixes:
   * Expose debugDumpRenderTree() outside debug mode.
   * Logger.supportsColor was missing a getter.
   * Mention in the usage docs that --hot requires --resident.
   * Trivial style fixes.

* This reverts commit 5e7e7b6e.

* default to lib/main.dart

This reverts commit 32ad81c8.

* send the reload source command for ios simulators

* review changes

* rewrite w/ a completer

#4672