[B4B-D] Add a function to create `BookmarkParentFolder` from folder node

There are more occurrences in the UI code where a node needs to be
converted to a `BookmarkParentFolder`. Therefore, add a helper function
that relies on the node's properties like `type` and `is_permanent_node`
to create `BookmarkParentFolder`.

Bug: 364594278
Change-Id: I9f7ffd6686ca694d6e02d64b5dfedd0ab040719c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6049640
Reviewed-by: Mikel Astiz <mastiz@chromium.org>
Reviewed-by: David Roger <droger@chromium.org>
Commit-Queue: Monica Basta <msalama@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1388953}