- [x] Wire up dependency checker and plumb flags down to the right place

Fixes #7014

This removes direct file access from within flutter_tools
in favor of using `package:file` via a `FileSystem` that's
accessed via the `ApplicationContext`.

This lays the groundwork for us to be able to easily swap
out the underlying file system when running Flutter tools,
which will be used to provide a record/replay file system,
analogous to what we have for process invocations.

* reapply handle new Observatory URL changes
Fixes https://github.com/flutter/flutter/issues/6843

* allow non numeric IPv4 addresses
Fixes https://github.com/flutter/flutter/issues/7051

https://github.com/flutter/flutter/commit/737a55ef3e47036220e72f3b3e17353d461b5fab

- [x] Make iOS and Android application startup paths consisitent.
- [x] Remove the now unncessary Android specific special cases from the runners.

* Allow for application-specific log readers.

When running with prebuilt application binaries, those applications
aren't guaranteed to be named "Runner" (as it is when we build
the app locally in Flutter tools)

* 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.

* make showElapsedTime default to true

* support nested progresses

* improve hot reload message

* rethrow

* implement app.stop() for release runs

* update comment

Disable features of `flutter run` that depend on the service protocol when running in release mode (#6571)

Fixes #4166.
Fixes #5120.
Fixes #5399.
Fixes #6507.

* add a pause parameter to the reload command

* encode OperationResult as json

* reverse isOk logic

Fixes #6283

* use less granular progress

* update restart text

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

Fixes https://github.com/flutter/flutter/issues/5468

* fix an issue where --hot would not exit

* add type annotations

* send the base uri back to debuggers

* add a fullRestart parameter to app.restart

* add await

* 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.