Can not use Command-ArrowDown to open an editor from a search match

[kieferrm]

While testing #12519.

• VSCode Version: 1.6.0 insiders
• OS Version: MacOS

Steps to Reproduce:

1. open a folder
2. Shift+Command+F
3. type a search expression with guaranteed matches
4. Tab to the search results view
5. Use ArrowDown and ArrowRight to navigate to a match
6. Use Command-ArrowDown to open the match in an editor
   -> no editor opens

[sandy081]

@kieferrm Command-ArrowDown is specific to open a file from the Explorer. I think it was used because Enter on a file is taken for rename in general in Mac.

In other views like Search & Problems following is supported

• Enter opens and pins the file and highlights the result
• Space opens the file without pinning and highlights the result

Also results displayed in these views are files, instead Search Matches or Problems.