Remove obsolete Mac flipped coordinates comment.

third_party/WebKit/Source/platform/Widget.h

Index: third_party/WebKit/Source/platform/Widget.h
diff --git a/third_party/WebKit/Source/platform/Widget.h b/third_party/WebKit/Source/platform/Widget.h
index 06e035f025d7f2823f426449f200bab0dd8b543c..d0c5c3899f13cf3356fa449c0ddbba5a51600577 100644
--- a/third_party/WebKit/Source/platform/Widget.h
+++ b/third_party/WebKit/Source/platform/Widget.h
@@ -92,10 +92,6 @@ public:
 
     virtual void handleEvent(Event*) { }
 
-    // It is important for cross-platform code to realize that Mac has flipped coordinates. Therefore any code
-    // that tries to convert the location of a rect using the point-based convertFromRootFrame will end
-    // up with an inaccurate rect. Always make sure to use the rect-based convertFromRootFrame method
-    // when converting window rects.
     IntRect convertToRootFrame(const IntRect&) const;
     IntRect convertFromRootFrame(const IntRect&) const;