This makes command validation happen as part of `verifyThenRunCommand()`,
using a newly introduced protected method (`validateCommand()`) rather than
a `commandValidator` property (that subclasses were responsible for manually
invoking).

This picks up a skia roll, which fixes some black screens on Android emulator.

It was incorrectly added in #11858

Fix the documentation (it was just wrong before).

Add an explicit code path to handle horizontal overflow so that we
don't have a left bias.

Just some very minor tweaks to remove subtle LTR bias.

We use the same arrow rotation animation in RTL and LTR, but I think
that's correct. Usually, rotations are either clockwise or
anitclockwise, which are the same in RTL and LTR. We might need to check
with someone who reads an RTL language to confirm.

Fixes #11845

This widget makes it easier to animated Positioned widgets with
awareness of the ambient Directionality.

Fixes #11998

Previously, the rows and columns arguments had different semantics. Now
they have the same semantics. The new API also uses Iterable rather than
List to give clients more flexiblity in how they construct these
arguments. For example, RenderTable no longer needs to reify the
reversed list of column positions.

Also, fix asserts in TableBorder#paint to match documentation.

Fixes #12009

After all my recent refactorings, some of the names were not really reasonable any more.

* internationalize time numerals

* tests

* use foundation.dart instead of meta.dart

* address comments

* Pin all dependencies ONCE AND FOR ALL

This replaces the secret `flutter update-packages --upgrade` with a destructive `flutter update-packages --force-upgrade` that actually goes and pins every dependency and transitive dependency in every flutter package to the same version.

* Add comments.

* introduce localized text geometry in MaterialLocalizations

* remove geometry from color text themes

* fix merge conflict

* optional Localizations

* fix fallback; test; docs

* misc .arb fixes; localizations validator

* regenerate localizations

* address comments

* do not treat plural variations as invalid keys

This is the last class other than BoxDecoration in this file, so by
extracting it we finally have all the parts of BoxDecoration
extracted.

This reverts commit 4a04de5e.

* Fix inherited widget notifications in Localizations

* address comments

* Revert "Pin args to 0.13.7 to avoid version conflict (#12208)"

This reverts commit 63802b3d.

* Revert "LinearGradient and RadialGradient RTL (#12204)"

This reverts commit daedbc84.

To make it cleaner when we RTLify these.

* Refactor CupertinoScaffold

* Rename rootTabPageBuilder to tabBuilder

* fix tab transparency padding

* add a CupertinoTab

* Add default background color

* Add a bunch of examples

* A bunch of tests

* Refactor CupertinoScaffold

* Rename rootTabPageBuilder to tabBuilder

* fix tab transparency padding

* Add default background color

* review notes

* fix test

* review

* Rename CupertinoTab to CupertinoTabView

* remove final ; in sample code for analyzer

* Refactor CupertinoScaffold

* Rename rootTabPageBuilder to tabBuilder

* fix tab transparency padding

* Add default background color

* review notes

* fix test

* round 3

* partially address comments

* merge

* review notes

* review

* review

* review