Bug 432131 – [10.4] Slight delay / flash / lag when window loses focus. r=josh, sr=roc

widget/src/cocoa/nsWindowMap.mm

@@ -317,6 +317,8 @@
   } else if ([window isSheet]) {
     [TopLevelWindowData activateInWindow:window];
   }
+  
+  [[window contentView] setNeedsDisplay:YES];
 }
 
 - (void)windowResignedKey:(NSNotification*)inNotification
@@ -329,6 +331,8 @@
   } else if ([window isSheet]) {
     [TopLevelWindowData deactivateInWindow:window];
   }
+  
+  [[window contentView] setNeedsDisplay:YES];
 }
 
 // The appearance of a top-level window depends on its main state (not its key