dijit.layout.ContentPane layout related DOH test

Tests ContentPane in it's role as a layout widget, including as child of another layout widgets (especially TabContainer).

Tests that href gets loaded when ContentPane is first made visible:

initially selected pane
unselected pane
initially selected inner pane
unselected pane
left pane
center pane

Tests for resizing in a layout container hierarchy:

initially selected pane
hide the second widget to see if ContentPane can still find it
ending text

Tests that ContentPane resize doesn't trigger reload:

initially selected pane
unselected pane

Test the ContentPane loads href and resizes children (as per it's contract a layout widget) when it's not a child of a layout container itself: