Reduce update delay when resizing with mouse.

By forcing an update of the text view at the end of batch processing of draw
commands the update delay when dragging to resize is reduced.

src/MacVim/MMVimController.m

@@ -905,6 +905,11 @@ static NSTimeInterval MMResendInterval = 0.5;
     }
 
     [textStorage endEditing];
+
+    // NOTE: During resizing, Cocoa only sends draw messages before Vim's rows
+    // and columns are changed (due to ipc delays). Force a redraw here.
+    [[windowController vimView] displayIfNeeded];
+
 #if MM_DEBUG_DRAWING
     NSLog(@"<==== END   %s", _cmd);
 #endif