double clicking file in working set causes editor to lose focus

[joelrbrandt]

Note: switching between files in the working set is designed to only require a single click. When users single click, this bug is NOT present (i.e. things work correctly).

However, since a double click in the "project files" list adds things to the working set, it's probable that users will occasionally double click inside the working set

To reproduce:

1. Add >=2 files to working set
2. Type in editor
3. Double click a different file in working set
4. Attempt to type -- editor is no longer focused

Expected:
Typing after double click should add text to the editor that contains the newly-selected file.

[peterflynn]

Fix has been merged

[joelrbrandt]

Looks great! Closing.