_generateError = function StackTrace$$GenerateError() {
        try {
            // Error must be thrown to get stack in IE
            throw new Error();
        } catch (err) {
            return err;
        }
    }
Given a StackFrame, seek source-mapped location and return new enhanced StackFrame.

@param {StackFrame} stackframe
@returns {Promise} that resolves with enhanced StackFrame.