This fix an error when compiling with Closure Compiler:
JSC_UNDEFINED_VARIABLE. variable e is undeclared at ~/CodeMirror/lib/codemirror.js line 1331 : 27
It might be good to use function(e) for all event listeners but I only changed the line that causes the error.
Add missing argument in event listener
Oh, that was bad. Thanks for catching it. Merged.