Avoid a crash where oldSelection changes while in selectionDidChange, invalidating the selection. Issue 3059.
Fix a bug where reloading profiles caused the window to shrink because PTYSession's setFont:nonAsciiFont:horizontalSpacing:verticalSpacing: thought that the non-ascii font had changed when it hadn't because PTYTextView was reporting the ascii font since using non-ascii font was off. Fix refs to PTYTextView's font and nonAsciiFont to use dot notation.
cited from http://d.hatena.ne.jp/mrkn/20101031/1288487978