Rename App to MaterialApp

MaterialApp assumes that you're using material design.

Also move radial reaction and fix imports for stats box.

Split material design widgets out of widgets.dart

Relative paths in internal flutter libraries

These are now part of material.dart.

Now that you import a top-level file for each layer of the Flutter
framework, within the framework we can use relative paths without being
worried about the copy/pasta problem we used to have.

Mistakenly broke sky_viewer.mojo.

Introduce IO thread for background tasks

Instead of joining the UI thread to copy data from the network into a buffer,
we now drain the data pipe for image decoding on a background thread.

Currently we run some tasks on the UI thread that shouldn't block the frame,
such as decoding images. This patch introduces a background thread on which we
can run these tasks.

Have Flat buttons set their default text styles.

Also, have dialog buttons use the accent colour.
Also, generally rationalise some of this stuff to match Material better.

Adds support for keeping track of contact points in physics

Changing themes caused crash

The root cause was that we crawled the tree to mark anyone who depended
on the updated theme dirty _after_ we crawled it to rebuild it. Thus, if
anyone was already marked dirty when the process started, then got
marked clean by the first (rebuild) walk, then got marked dirty again by
the notification, they'd be clean when they got the notification,
despite already being in the dirty list, which would cause an assertion.

Also IconTheme didn't have an operator==, so it was independently too
aggressive about updates.

Add an isEmpty property to Rect

Also trace image decoding.

Defunct DismissableState should not have live animations

Drawer test.

Format trace file names so they are easier to organize

Allow Stacks with no children or only poisitioned children

Remove ButtonState

SnackBar throws exception on creation

Clients should just use a GestureDetector (or an InkWell) instead.

Indexed stack

Added horizontal and vertical alignment properties to Stack so that the origin of non-positioned children can be specified. Currently all of the non-positioned children just end up with their top-left at 0,0. Now, for example, you can center the children by specifying verticalAlignment: 0.5, horizontalAlignment: 0.5.

Added IndexedStack which only paints the stack child specified by the index property. Since it's a Stack, it's as big as the biggest non-positioned child. This component will be essential for building mobile drop down menus.

Added a (likely temporary) example that demonstrates IndexedStack.

Added horizontal and vertical alignment properties to Stack so that the origin of non-positioned children can be specified. Currently all of the non-positioned children just end up with their top-left at 0,0. Now, for example, you can center the children by specifying verticalAlignment: 0.5, horizontalAlignment: 0.5.

Added IndexedStack which only paints the stack child specified by the index property. Since it's a Stack, it's as big as the biggest non-positioned child. This component will be essential for building mobile drop down menus.

Added a (likely temporary) example that demonstrates IndexedStack.

It was trying to grab the route's performance before it was created. Now we
create the performance eagerly again.

The Drawer should animate out when popped off the navigator

FlatButton highlights but doesn't tap around edge

Adds support for applying forces and impulses to sprite physics

BoxConstraints.toString() should show closed intervals