This also fixes a bug that was preventing markNeedsLayout from working

R=abarth@chromium.org, eseidel@chromium.org, abarth, eseidel

Review URL: https://codereview.chromium.org/1160013004

This CL introduces RenderStack and fixes a number of bugs to make the Drawer in
components2 work.

R=ianh@google.com, eseidel@chromium.org

Review URL: https://codereview.chromium.org/1147143005

These transforms are currently very basic but they seem to mostly work.

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/1152273004

Looks horrible.  But it's a start.

R=abarth@chromium.org, ianh@google.com
BUG=

Review URL: https://codereview.chromium.org/1146913005

This CL is a first pass at implementing container in fn2. In this approach,
Container is a Component that builds a number of RenderNodeWrappers depending
on what is needed.

R=ianh@google.com

Review URL: https://codereview.chromium.org/1158983005

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/1166773003

This machinery existed only to save one null check.

R=ianh@google.com

Review URL: https://codereview.chromium.org/1163933002

BlockContainer uses a RenderBlock to lay out its children.

R=eseidel@chromium.org, jackson@chromium.org

Review URL: https://codereview.chromium.org/1166473005

Prevously we listened for events on the document and then walked up the
component hierarchy looking for EventListenerNodes. Now we do something similar
by hooking the event dispatching logic in the AppView.

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/1153343004

Previously layout2.dart was a thousand lines long.

R=ianh@google.com

Review URL: https://codereview.chromium.org/1161003002

R=ianh@google.com

Review URL: https://codereview.chromium.org/1150253005

R=ianh@google.com

Review URL: https://codereview.chromium.org/1160843005

R=ianh@google.com

Review URL: https://codereview.chromium.org/1156303004

This dramatically simplifies the layout model.
I haven't gone through and simplified the existing functions, we should probably go through and figure out if they can be cleaned up a bit.

R=abarth@chromium.org

Review URL: https://codereview.chromium.org/1161983004

R=ianh@google.com

Review URL: https://codereview.chromium.org/1156013003

This gets things off the ground barely enough to show some pixels.
These are not pixels that are actually part of the stock app, but
it's a start.

R=abarth@chromium.org

Review URL: https://codereview.chromium.org/1157033006

This is needed for cases where the UINode doesn't have a list of
children (so it doesn't go through the RenderNodeWrapper sync logic
that removes children), but it still has multiple slots, and needs to
support removing nodes from those slots. (For example, removing a
drawer from a ScaffoldContainer.)

Also, expose syncChild (it used to be private) so it can be overridden
in descendants outside fn.dart.

R=abarth@chromium.org

Review URL: https://codereview.chromium.org/1158563003

This is needed to create a ScaffoldContainer in scaffold.dart.

This exposes:
  UINode._root => root
  UINode._removeChild => removeChild
  RenderNodeWrapper._createNode => createNode
  RenderNodeWrapper._emptyNode => emptyNode
  RenderNodeWrapper._syncRenderNode => syncRenderNode

R=abarth@chromium.org

Review URL: https://codereview.chromium.org/1148323004

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/1156543004

Before, OneChildListRenderNodeWrappers were responsible for removing
the child nodes' RenderCSS nodes from their containers, and for moving
those around when nodes were reordered. Now, they're also responsible
for adding them.

R=abarth@chromium.org

Review URL: https://codereview.chromium.org/1145953003

[Effen] Try to catch more misuse of fn by asserting that UINode nodes are only built when we're updatin the tree.

R=abarth@chromium.org

Review URL: https://codereview.chromium.org/1148253002

R=abarth@chromium.org

Review URL: https://codereview.chromium.org/1145623003

R=abarth@chromium.org, eseidel@chromium.org

Review URL: https://codereview.chromium.org/1149533002

NOTE: This CL appears far larger than it actually is for two reasons:

1) Many files were moved around to use the Dart package directory structure.
2) Many .dart files had to have import paths updated.

- Organize mojo/public/dart so that it uses standard Dart package layout
- Organize mojo/dart/apptest so that it uses a standard Dart package layout
- Organize sky/sdk so that it uses a standard Dart package layout
- Create a mojo/testing package (used by unittests)
- Introduce the 'dart_pkg' gn rule which populates gen/Config/dart-pkg
- All internally vended Dart packages must have a corresponding dart_pkg rule
- It is now possible to use dependency_overrides: in pubspec.yaml to mix internal and external package dependencies (enables analyzer, editor, webstorm usage for internal developers).
- Package root for dart content handler ends with "packages/"
- Imports of mojo package uris no longer need the "public/dart"
- mojo/public/tools/dart_package.py is a clone of mojo/public/tools/gn/zip.py
- Sky tests no longer run 'deploy_sdk' script.

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/1132063007

The style syncing logic that was in OneChildListRenderNodeWrapper is now in RenderNodeWrapper.
TextFragment and Image now just inherit directly from RenderNodeWrapper.
OneChildListRenderNodeWrapper now only deals with syncing children.

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/1142123004

R=abarth@chromium.org

Review URL: https://codereview.chromium.org/1128803007

[Effen] Rename SkyNodeWrapper and SkyElementWrapper to match their current actual roles, RenderNodeWrapper and OneChildListRenderNodeWrapper.

This lays the groundwork for supporting RenderNode classes that have more complicated child setups.

R=abarth@chromium.org

Review URL: https://codereview.chromium.org/1134303006

This creates a new RenderNode class that does positioning.
It then creates an fn Container class that uses it just to position things at 0,0 at the full extent of the container.

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/1128103009

Previously, the fn "Text" class rendered as a single block of text.
Now, there's a "Paragraph" class that contains "TextFragment"s, and "Text" is just a component that places a single TextFragment into a single Paragraph.
This allows other components, notably the Input component, to build more complicated paragraphs of styled text, without using 'display'.

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/1139123007

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

- 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

This introduces a new kind of ContentNode similar to Style but which
instead of changing the styles that apply to the node, provides new
settings to apply to the "parentData" structure.

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/1122413006

This reverts commit 1a4db2e964de8a2eba7c76c0904027150cc0c387.

This broke the bots.

TBR=github.com@spam.hixie.ch

Review URL: https://codereview.chromium.org/1137153002

This introduces a new kind of ContentNode similar to Style but which
instead of changing the styles that apply to the node, provides new
settings to apply to the "parentData" structure.

If you have better ideas for the class names here let me know.

Note that the layout.dart backend of this is hacky (more so than
before, even); once we have something other than the DOM and CSS to
back it, it'll get rewritten.

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/1129893006

FlexContainer is a (pretend) new layout primitive that implements Flex layout.
It's only pretend because right now it's still just backed by CSS.
This is a step along the way to removing all the CSS from fn.

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/1128743003

[Effen] Port fn.dart from the legacy sky.Node backend to the RenderNode backend, which is currently just a sky.Node-backed shim, but will eventually be the core Sky interface for layout and painting.

- the custom layout class in fn is removed by this patch; a new class
  will be added in a later CL

- the version of layout.dart in this CL is a subset of what we're
  targetting on the long run with
     https://codereview.chromium.org/1093633002

- a couple of lines of dead code are removed in this CL also

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/1117143003

Pipe the remaining time for an animation all the way out to the AnimatedValue.
Make splashes abortable, which causes them to continue to fade but no longer grow, by having them fade in 100ms or however long the animation was still going to go for, whichever is quickest.
Make Scrollables support objects registering with them to be told when scrolling happens.
Make UINode support subclasses being informed when _remove() was called.
Hook all that together to make splashes go away when scrolling by having them register with any ancestor Scrollables such that when those scroll, all the splashes get aborted. Unregister when removed.

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/1092423003

otherwise when you switch from one Container instance to another, you
end up with the the layout being done by the wrong instance.

R=ojan@chromium.org

Review URL: https://codereview.chromium.org/1086983004

[Effen] Custom layout. For now, FixedHeightScrollable uses a custom BlockLayout algorithm, mostly as a proof of concept.

R=ojan@chromium.org

Review URL: https://codereview.chromium.org/1064983002

element with display:paragraph, so that the C++ side shares RenderStyles.
(based on review comments on https://codereview.chromium.org/1078973002 )

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/1070243003