Changed single selection to multiple selection for Recent, OneDrive and Site Files tabs in FilePicker component

[MonalisaBaltatescu]

…s for FilePicker component

Q	A
Bug fix?	[ ]
New feature?	[x]
New sample?	[ ]
Related issues?	fixes #725

What's in this Pull Request?

The current version of the FilePicker doesn't support multiple selections for files.
I have changed the selection mode to multiple for Recent, OneDrive and Site Files tabs.
The folders cannot be selected but could be opened and multiple selections apply inside.

[MonalisaBaltatescu]

@joelfmrodrigues could this PR be closed and merged now that the target branch is master?

[joelfmrodrigues]

@MonalisaBaltatescu just tested the PR and it's great! Thank you for the improvements.
While testing it, I found just an error on the console when selecting folders (tested using the Site option):

1. Select a folder from a document library in a SharePoint site
   

2. The following error is logged:
   

3. This is the code generating the error (line 459):
   

Is this line required to handle folders? I tried to comment it and it seems to behave the same, although it could be because of the error not allowing it to behave the same way you expected.

Other than that, all looks good and ready to go ☺️

[joelfmrodrigues]

Hi @MonalisaBaltatescu

just checking if you would be able to advise on the above?

[MonalisaBaltatescu]

Hi, I’m working on it. Just need more time ☺️

[estruyf]

@MonalisaBaltatescu I have no idea why the PR got closed. Going to re-open it.

[joelfmrodrigues]

@MonalisaBaltatescu sorry to chase you again with this, but just wondering if you need some help?

[MonalisaBaltatescu]

@joelfmrodrigues I am sorry for the delay, didn't have the time lately. Please check now and let me know if there are any other issues

[joelfmrodrigues]

@MonalisaBaltatescu many thanks for the update and absolutely no need to apologise as these are voluntary contributions - I am also having issues finding the time to contribute myself

I have tested it and all seems to be working fine, many thanks