Add null-check for request before checking SelectedItem on global search

[IsakNaslundBh]

Issues addressed by this PR

Closes #675

Adding simple null-check on request before trying to access SelectedItem.
See issue as to why/when this has been slightly annoying issue.

Test files

Global search should still work.

Changelog

Additional comments

Cannot really see how this could have a negative impact on anything, but glad for a quick look @adecler

[adecler]

I don't see any reason why a null check would be a problem here. Approved!

[IsakNaslundBh]

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[FraserGreenroyd]

As per @adecler - can't see this hurting anything. But I look forward to being proved wrong in 3 weeks time...

[bhombot-ci]

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[IsakNaslundBh]

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