UpdateZoomControls honors the global enabled state of the zoom commands....

chrome/browser/views/wrench_menu.cc

Index: chrome/browser/views/wrench_menu.cc
===================================================================
--- chrome/browser/views/wrench_menu.cc	(revision 53070)
+++ chrome/browser/views/wrench_menu.cc	(working copy)
@@ -456,10 +456,17 @@
     bool enable_increment, enable_decrement;
     int zoom_percent =
         static_cast<int>(GetZoom(&enable_increment, &enable_decrement));
+    enable_increment = enable_increment &&
+        menu_model_->IsEnabledAt(increment_button_->tag());
+    enable_decrement = enable_decrement &&
+        menu_model_->IsEnabledAt(decrement_button_->tag());
+    increment_button_->SetEnabled(enable_increment);
+    decrement_button_->SetEnabled(enable_decrement);
     zoom_label_->SetText(l10n_util::GetStringF(
                              IDS_ZOOM_PERCENT, IntToWString(zoom_percent)));
-    increment_button_->SetEnabled(enable_increment);
-    decrement_button_->SetEnabled(enable_decrement);
+    // If both increment and decrement are disabled, then we disable the zoom
+    // label too.
+    zoom_label_->SetEnabled(enable_increment || enable_decrement);
   }
 
   double GetZoom(bool* enable_increment, bool* enable_decrement) {