Issues/48903 makes focus traversal more robust - #50522

Description

When sets canrequestfocuse= false on a focusScopeNode that is currently focusing one of its child, the focus manager will call unfocus on the current focused child and refocus previous focused child in the tree. However, the search only go one level up in the focus tree. If it cannot find a node to focus in this level, it exit silently and refocus the root focus node.

I updated the logic so that it will search up the tree until it reach the root.

Related Issues

#48903 (comment)

Tests

I added the following tests:

"focus traverse correct when pop mutiple page simultaneously - with focused children"

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Breaking Change

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