// Subclasses should implement the work they need to do in MessagePump::Run
// in the DoRun method. MessagePumpCFRunLoopBase::Run calls DoRun directly.
// This arrangement is used because MessagePumpCFRunLoopBase needs to set
// up and tear down things before and after the "meat" of DoRun.
// Subclasses should implement the work they need to do in MessagePump::Run
// in the DoRun method. MessagePumpCFRunLoopBase::Run calls DoRun directly.
// This arrangement is used because MessagePumpCFRunLoopBase needs to set
// up and tear down things before and after the "meat" of DoRun.