Now we just have one TextSpan class that handles both simple strings, trees of
children, and styling both. This approach simplifies the interface for most
clients.

This patch also removes StyledText, which was weakly typed and tricky to use
correctly. The replacement is RichText, which is strongly typed and uses
TextSpan.

Keep AnimationController's _value in bounds

additional validation for device commands

Remove all inline templates and provide a way to specify templates as resources

Rather than clamping _value on read, we now clamp the value when writing it,
which simplifies reasoning about _value.

support waiting for things to happen in Flutter Driver

Test BottomSheet rebuilding with ScaffoldFeatureController.setState()

Enumerate lints for analysis in synthesized options file.

Moved the Gallery's home page padding inside its Block

Gallery List Demo

# Conflicts:
#	packages/flutter_tools/lib/src/commands/analyze.dart

This enables us to exclude `library_names` pending a new stable SDK push (see notes: https://github.com/flutter/flutter/pull/1996).  Also excluded are a few lints who's feedback was just getting regexp'ed out.  Moving forward, this will allow us to selectively enable specific lints of interest as well.

Move style guide to website.

Trivial cleanup of getDistanceToBaseline

Turns out we don't need 'parent' outside the assert at all.

Fix --debug

Clean up scroll behaviour.

Remove redundant Material from start project

This makes ScrollBehavior agnostic about the kind of scroll.
This also means ExtentScrollBehavior's comment about being linear is
more relevant (previously it was true of all scroll behaviours).

add a validator for Atom

...and some style nits.

Depends on https://github.com/flutter/website/pull/177

Some trivial animation library cleanup.

more details in infra/README.md

"flutter create" can generate a basic driver test; "flutter drive" gains new options

"flutter create" adds option `--with-driver-test` that adds
dependencies to `flutter_driver` in `pubspec.yaml` and creates
a basic driver test runnable via `flutter drive
--target=test_driver/e2e.dart`

"flutter drive" new options:

- `--keep-app-running` tells the driver to not stop the app after tests
  are done
- `--use-existing-app` tells the driver to not start a new app but use
  an already running instance

fix a checked mode assertion

This enables us to exclude `library_names` pending a new stable SDK push (see notes: https://github.com/flutter/flutter/pull/1996).  Also excluded are a few lints who's feedback was just getting regexp'ed out.  Moving forward, this will allow us to selectively enable specific lints of interest as well.

remove iosSimulator field from ApplicationPackageStore