Instead of embedding Flutter.framework and BuildFlutterApp in the Xcode
project, we store these in flutter.git, where we can reference them.

We'll use this functionality to implement some subtle behaviors for tooltips.

* modernize `flutter drive` w.r.t. debug/profil/release options

* make error message prettier

There are still many more left before rendering.dart is complete.

Bump dart SDK to 1.17.0-dev.6.

Remove spurious padding.

Fixes #3980
Fixes #3560

We now explain what coordinate system each argument is expected to be in.

Fixes #4205

* working on making a faster flutter run restart

* clean up todos; fire events on isolate changes

* use the Flutter.FrameworkInitialization event

* review comments

* resolve symlinks in paths to flutter

* review comments

We weren't listening to the decorations to see when they loaded.

Fixes #4185

This reverts commit 8f69cccc.

The new version has an API change. Also, up our SDK requirements to be a
bit more realistic.

* dissallow -release mode on emulators

* have the help text print the default mode

New dev build with more fixes and (fingers-crossed) speed-ups.

Fixes #4186

* fixed issue #4179 bin/flutter fails when linked with relative symlink

* fixed issue #4179 bin/flutter fails when linked with relative symlink

* My second attempt at following symlinks correctly

* compress text assets for docs, when uploading

* reorder args

* ensure old files are deleted

* recurse on the cp

* set source path correctly

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

This reverts commit d4d74d9c.

Address feedback from material design team.

Fixes #4144
Fixes #4145
Fixes #4146

For consistency.

Fixes #4142

Fixes #4114

When building AOT, we now run `pub get` instead of printing an error telling
the user to run `pub get`. We can remove this code once the bug reference above
is fixed (should be a couple days).

* iOS tools cleanup

1) Fix `flutter install` on both device and simulator to refer to the actual
   bundle and not just the .generated folder
2) Fix `flutter run` on device to actually run vs just installing

Still TODO:
1) Discovered that isAppInstalled on iOS simulator always reports true,
   meaning it'll never actually try to install the app.

Fixes #3947
Fixes #1823