And also Material Design of course.

@abarth

This introduces the concept of an Anchor, which you can use to link
transitions together. I've used this in the Fitness and Stocks apps to
link the FAB and SnackBar to animate together by sharing the
SlideTransition.

I also fixed the Scaffold hit testing code to apply sub-widget
transforms, so it works with Transformed nodes.

R=abarth@chromium.org

Review URL: https://codereview.chromium.org/1218593002.

We already know how to talk to the network_service from Dart
via fetch.dart.  Might as well use that for Image loading
as well insetad of having ImageLoader do it.

As part of this I've renamed *ImageLoader to *ImageDecoder
and moved all the image loading logic into Dart.  This required
me to teach the idl system about mojo handles so that I could
pass the resulting MojoHandle from fetch.dart up through to
ImageDecoder.

R=abarth@chromium.org, jackson@google.com, hansmuller@google.com

Review URL: https://codereview.chromium.org/1173703002.

R=abarth@chromium.org

Review URL: https://codereview.chromium.org/1133353008

Revert "Add library names to many sky libraries"

This reverts commit 1337e0a803a54ee92d6dce7f8c4a6335f7cbb9fa.

BUG=
R=abarth@chromium.org

Review URL: https://codereview.chromium.org/1142893007

- Analyzer complains about libraries not having names. This adds names to many libraries.

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/1150433002

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/1132983007

Changes:
- adds a couple of radio buttons to the drawer menu list.
- makes menu items support being tapped and reporting the tap.
- hooks up the checkbox to actually support being checked.
- changes the drawer menu items to make more sense in a stock app.

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/1137373004

This is a prerequisite to dropping 'display:none'.
Included in this CL is making AnimatedValue able to animate more than one field.

R=abarth@chromium.org

Review URL: https://codereview.chromium.org/1126333006

- add a checkbox to the stock app, so that we're testing the checkbox widget
  (it's not currently wired up to anything, that can come later)
- make InkSplash use FlexContainer so that we can use flex in the popup menu items
- make effen's Text be more similar to Image and Container, so that it can be styled
- make layout.dart's RenderCSSText correctly support being styled
- also fixes a bug with the stock list where we were rendering one too few a row when scrolling
- check in the code to dump the DOM so I don't have to keep remembering how to do this

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/1134163003

Analyzer was complaining about '-' not being an allowed character
in dart file names.

R=jamesr@chromium.org

TBR=eseidel

Review URL: https://codereview.chromium.org/1065653009

remove members that are never read
remove imports that are never used

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/1099203002

- make the ScrollBehavior instance long-lived, rather than recreating
  it each time we update the list contents.
- have OverscrollBehavior track the total height of the contents and
  the height of the scrollable region, so that it can determine when
  to stop scrolling down.
- teach OverscrollBehavior about how to determine when to stop
  scrolling down, and how to bounce when it's too far down.
- replace the 'energy' concept in Particles with a method that sets
  the energy and direction at the same time, instead of assuming that
  the direction is always positive when setting energy.
- make FixedHeightScrollable lists track the number of items in the
  list and have them update their ScrollBehavior regarding this
  information as it changes.
- track how many items are currently showing in the list stock list.

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/1097373002

[Effen] Only skip rows we're showing, when skipping past the rows that we've scrolled beyond in the stock list.

Currently, if you then scroll down N items with a filter set, we select which
stock to show by taking the entire list of stocks, skipping the first N, then
filtering the list, then selecting as many stocks as needed to fill the list.

So suppose the list is A, B, Cx, Dx, Ex, F, and the filter is "x", and you've
scrolled down 1 item.

Currently we'd show Cx, Dx, Ex.

Scroll down 1 again.

We still show Cx, Dx, Ex.

What we _should_ show is Dx, Ex if you've scrolled down 1, and just Ex if you've
scrolled two.

This patch fixes this. We now skip rows _after_ filtering. This fixes
the bug whereby if you set a filter then fling the list, we show the
same item over and over as if in a loop.

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/1057603006

-Make display:flex, flex-direction: column, flex-shrink: 1 the default.
-Simplify StyleAdjuster::adjustStyleForAlignment to remove special cases we
won't need as we make flex the default and remove absolute positioning.
-Fix a bug this exposed in column flexboxes where we'd apply the wrong edge
of border/padding/margin.
-For now leave the default of align-items:stretch. The main change here is
that iframe/img will do width:auto the same as blocks (i.e. the width of
the parent). I think this is a good change, but we'll have to see how it feels
in practice.

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/1061163002

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/1043283003

1) Merge input example into widgets example
2) Move single-file, non-fn examples into a "raw" directory
3) Rename stocks-fn and widgets-fn to stocks and widgets

R=ojan@chromium.org

Review URL: https://codereview.chromium.org/1005393006