- Share common layout logic between `Border`, `ContentPresenter` and `ScrollContentPresenter`
- Added a bunch of tests for things not previously convered
- Fix `ScrollContentPresenter` child layout
`VisualBrush`es need to get delegated back to the renderer for
rendering, so added an `IVisualBrushRenderer` interface which is
implemented by the renderers, and pass this when creating drawing
contexts. Only currently implemented/tested for D2D and
`ImmediateRenderer`.
There are still a few bugs around scrollbar behavior, and maybe Grid. To
see them, add a long item in the middle of VirtualizationTest's items,
resize the window to require a scrollbar and scroll up and down.
Rather than repainting whenever, this adds a render loop which is called
N times per second. IRenderQueueManager and ITopLevelRenderer have been
removed, replaced by IRenderer.
Don't add virtualized items before the virtualizing panel is attached to
the visual tree, as bindings etc won't be set and so measurement will
produce 0,0 causing all items to be materialized.
Steven Kirk
Nikita Tsukanov
Steven Kirk
donandren