Since we can change the theme's platform, we need to make sure we
propagate that throughout rather than having half the app use the native
platform and half the app use the selected platform.

Add some docs to explain how to use setState() wiht Checkbox, Radio,
Slider, and Switch.

Based on experience of usability study participant P1.

This tries to capture some of the experience of usability study
participant P1.

This is loosely based on the experience of usability study participant P1.

Based on observations of usability study participant P1.

This partially reverts https://github.com/flutter/flutter/issues/626 ,
but horizontal padding is not in the spec, so we still match the spec.

Also remove the obsolete "flutter refresh" command

This patch makes it possible to build Flutter apps that use the framework on
Fuchsia.

Fixes #5843

We'll eventually remove HostMessages because it's just a pass-through to
PlatformMessages, but that will be a separate step.

This patch removes our dependency on asset_bundle.mojom.

Required for compatibility with older versions of Android

This patch removes uses of keyboard.mojom in favor of the
TextInputPlugin.

This reverts commit 8f273e49.

If maxLines is 1, it's a single line Input that scrolls horizontally.
Otherwise, overflowed text wraps and scrolls vertically, taking up at
most `maxLines`.

Also fixed scrolling behavior so that the Input scrolls ensuring the
cursor is always visible.

Fixes https://github.com/flutter/flutter/issues/6271

They support multiline text now.

I based this on a conversation I had with @mpcomplete.

This class will eventually replace the Keyboard class we currently use. As part
of this migration, we'll switch from using mojom to interact with the IME to
using platform messages.

Fixes https://github.com/flutter/flutter/issues/6274

Bump to latest Dart SDK dev build (`1.21.0-dev.0.0`).

* updates to analyzer w/ support for bazel workspaces
* removes deprecated analysis `cacheSize` variable access

The circle's offset represents the position of a navigation button within the
row of buttons.  Previously, this offset had been applied to the entire width
of the bottom bar, not just the button region.

Fixes https://github.com/flutter/flutter/issues/6046