[dojox.layout] ExpandoPane doesn't handle being hidden initially

[dante]

The _titleHeight is calculated in startup, but should probably be extracted into a secondary function only fired once immediately before an initial resize() call, to ensure the pane is visible (like being in a selected tab) before doing the calculations and animation creation.

[bill]

See also #7299, that will be fixed at the same time, if you simplify that test case to not use the intermediate ContentPane's.

[bill]

I'm wondering if instead of changing ExpandoPane we should modify StackContainer so it doesn't call startup() until the first time a widget is shown.

[dante]

(In [16553]) fixes #8531 - defer resize until after initial visibility setup. also lots of css fixes. attemps to fix but does not #8569, though the tabs have the right height, their controller is too small. !strict