Improve conditional performance by memoizing branch widgets

[evshi]

Is your feature request related to a problem? Please describe.
Currently conditional widget lazily renders the widget when the condition is met.

Describe the solution you'd like
Memoize the widgets in each branch so they don't need to be re-rendered by React.

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.

Additional context
This should be helpful when conditionally rendering large widgets like DataGrids.