Note: This should only be set in the context of MountSpec.
public abstract boolean onMount
Note: This should only be set in the context of MountSpec. Will be ignored for
If this is true and this MountSpec is pureRender the mount process will check
shouldComponentUpdate before unmounting/mounting in place and only update the content if
necessary. If this is false instead, the mount process will only rely on the information
provided by the layout process.
As a rule of thumb this should only be set to true when for a Component the cost of calling
Mount/Unmount greatly exceeds the cost of calling ShouldUpdate.