Revert a change which broke the "Open/Copy Link" context menu items on the Mac sad tab.

chrome/browser/ui/cocoa/tab_contents/sad_tab_view_cocoa.mm

Index: chrome/browser/ui/cocoa/tab_contents/sad_tab_view_cocoa.mm
diff --git a/chrome/browser/ui/cocoa/tab_contents/sad_tab_view_cocoa.mm b/chrome/browser/ui/cocoa/tab_contents/sad_tab_view_cocoa.mm
index 503a7c8f907bfc02ca55ca66fc06a9d6978ad6e0..82c2980fbdb21a6b0a1955c9c9c5c2d946c66668 100644
--- a/chrome/browser/ui/cocoa/tab_contents/sad_tab_view_cocoa.mm
+++ b/chrome/browser/ui/cocoa/tab_contents/sad_tab_view_cocoa.mm
@@ -196,10 +196,4 @@ NSTextField* MakeLabelTextField(NSRect frame) {
   return YES;
 }
 
-- (NSRange)textView:(NSTextView*)textView
-    willChangeSelectionFromCharacterRange:(NSRange)oldSelectedCharRange
-                         toCharacterRange:(NSRange)newSelectedCharRange {
-  return NSMakeRange(0, 0);
-}
-
 @end