Pinned cross references or minigraph panes do not restore correctly when saved in layouts

[jonpalmisc]

Original bug report:

1. ~~Attempt to save a layout with a pinned cross references or minigraph pane.~~
2. ~~Enjoy crash.~~

Updated report:

Saving a layout with a pinned cross reference or minigraph does not restore them correctly.

[jonpalmisc]

The originally-reported crash should be fixed in builds ≥3588. The "Save Layout" feature still does not behave as expected in the described scenario, so this issue will remain open to track proper restoration of pinned panes.

[plafosse]

I reproduced this in 4.0. The mini-graph pop out works and restores properly the pinned cross references doesn't.

Repro Steps:

1. Open a binary
2. Open pinned xrefs
3. close the binary
4. re-open the binary
5. observe the pinned xrefs is gone