Add fixes for old xcodes

TmuxController.h

@@ -53,6 +53,7 @@ extern NSString *kTmuxControllerSessionWasRenamed;
     NSMutableSet *hiddenWindows_;
     NSTimer *listSessionsTimer_;  // Used to do a cancelable delayed perform of listSessions.
     NSTimer *listWindowsTimer_;  // Used to do a cancelable delayed perform of listWindows.
+    BOOL ambiguousIsDoubleWidth_;
 }
 @property (nonatomic, readonly) TmuxGateway *gateway;

TmuxWindowOpener.h

@@ -31,6 +31,7 @@ extern NSString * const kTmuxWindowOpenerStatePendingOutput;
     PTYTab *tabToUpdate_;
     id target_;
     SEL selector_;
+    BOOL ambiguousIsDoubleWidth_;
 }
 @property (nonatomic, assign) int windowIndex;