[folding] Code folding does not respect multi-cursor

<!-- Do you have a question? Please ask it on https://stackoverflow.com/questions/tagged/vscode. --> <!-- Use Help > Report Issue to prefill these. --> - VSCode Version: 1.20.1 - OS Version: Windows 10 Steps to Reproduce: 1. Open a new document with the following css: ``` .selector{ min-width: 40px; } .selector.a{ width: 468px; height: 60 px; } .selector.b{ width: 728px; height: 90 px; } .selector.c{ width: 160px; height: 600 px; } ``` 2. Highlight any occurrence of `.selector` and multiselect all occurrences with `Ctrl + D`. 3. Move all cursors to the beginning of their respective lines with `Home` 4. Attempt to execute a code fold with `Ctrl + Shift + [` Expected Behavior: All selectors are folded down to ``` .selector{…} .selector.a{…} .selector.b{…} .selector.c{…} ``` Actual Behavior: Only the initially selected selector is folded. All others remain expanded. <!-- Launch with `code --disable-extensions` to check. --> Does this issue occur when all extensions are disabled?: Yes