Add debug data for incorrect access to preferences by extension.

extensions/browser/extension_pref_value_map.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "extensions/browser/extension_pref_value_map.h"
 
 #include "base/prefs/pref_value_map.h"
 #include "base/stl_util.h"
 #include "base/values.h"
 
@@ skipping 53 matching lines @@
   if (prefs->RemoveValue(key))
     NotifyPrefValueChanged(key);
 }
 
 bool ExtensionPrefValueMap::CanExtensionControlPref(
     const std::string& extension_id,
     const std::string& pref_key,
     bool incognito) const {
   ExtensionEntryMap::const_iterator ext = entries_.find(extension_id);
   if (ext == entries_.end()) {
-    NOTREACHED();
+    NOTREACHED() << "Extension " << extension_id
+                 << " is not registered but accesses pref " << pref_key
+                 << " (incognito: " << incognito << ")."
+                 << " http://crbug.com/454513";
     return false;
   }
 
   if (incognito && !ext->second->incognito_enabled)
     return false;
 
   ExtensionEntryMap::const_iterator winner =
       GetEffectivePrefValueController(pref_key, incognito, NULL);
   if (winner == entries_.end())
     return true;
@@ skipping 308 matching lines @@
 
 void ExtensionPrefValueMap::NotifyPrefValueChanged(const std::string& key) {
   FOR_EACH_OBSERVER(ExtensionPrefValueMap::Observer, observers_,
                     OnPrefValueChanged(key));
 }
 
 void ExtensionPrefValueMap::NotifyOfDestruction() {
   FOR_EACH_OBSERVER(ExtensionPrefValueMap::Observer, observers_,
                     OnExtensionPrefValueMapDestruction());
 }