"Make all relevant" checkbox for subtrees

Does the following:<br>Ignores the page object, so if the page object is linked in a subtree, assume that any other behavior described below ignores it.<br>Shows as checked if all objects are relevant to page object<br>Shows unchecked otherwise<br>Does not show if nothing is mapped in subtree.<br>If clicked when checked, removes all direct mappings to page object (makes all "irrelevant")<br>If clicked when unchecked, makes direct mappings to page object for all non-relevant items

Ref: b/14494025