Cleanup: Simplify some extensions / content_settings Observer code by simply DCHECKING instead of u…

chrome/browser/content_settings/content_settings_default_provider.cc

 // Copyright (c) 2012 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 "chrome/browser/content_settings/content_settings_default_provider.h"
 
 #include <string>
 #include <vector>
 
 #include "base/auto_reset.h"
@@ skipping 262 matching lines @@
   DCHECK(prefs_);
   RemoveAllObservers();
   pref_change_registrar_.RemoveAll();
   prefs_ = NULL;
 }
 
 void DefaultProvider::Observe(int type,
                               const content::NotificationSource& source,
                               const content::NotificationDetails& details) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK_EQ(chrome::NOTIFICATION_PREF_CHANGED, type);
+  DCHECK_EQ(content::Source<PrefService>(source).ptr(), prefs_);
 
-  if (type == chrome::NOTIFICATION_PREF_CHANGED) {
-    DCHECK_EQ(prefs_, content::Source<PrefService>(source).ptr());
-    if (updating_preferences_)
-      return;
+  if (updating_preferences_)
+    return;
 
-    std::string* name = content::Details<std::string>(details).ptr();
-    if (*name == prefs::kDefaultContentSettings) {
-      ReadDefaultSettings(true);
-    } else if (*name == prefs::kGeolocationDefaultContentSetting) {
-      MigrateObsoleteGeolocationPref();
-      // Return and don't send a notifications. Migrating the obsolete
-      // geolocation pref will change the prefs::kDefaultContentSettings and
-      // cause the notification to be fired.
-      return;
-    } else {
-      NOTREACHED() << "Unexpected preference observed";
-      return;
-    }
+  const std::string& name = *content::Details<std::string>(details).ptr();
+  if (name == prefs::kDefaultContentSettings) {
+    ReadDefaultSettings(true);
+  } else if (name == prefs::kGeolocationDefaultContentSetting) {
+    MigrateObsoleteGeolocationPref();
+    // Return and don't send a notifications. Migrating the obsolete
+    // geolocation pref will change the prefs::kDefaultContentSettings and
+    // cause the notification to be fired.
+    return;
+  } else {
+    NOTREACHED() << "Unexpected preference observed";
+    return;
+  }
 
-    NotifyObservers(ContentSettingsPattern(),
-                    ContentSettingsPattern(),
-                    CONTENT_SETTINGS_TYPE_DEFAULT,
-                    std::string());
-  } else {
-    NOTREACHED() << "Unexpected notification";
-  }
+  NotifyObservers(ContentSettingsPattern(),
+                  ContentSettingsPattern(),
+                  CONTENT_SETTINGS_TYPE_DEFAULT,
+                  std::string());
 }
 
 void DefaultProvider::ReadDefaultSettings(bool overwrite) {
   base::AutoLock lock(lock_);
   const DictionaryValue* default_settings_dictionary =
       prefs_->GetDictionary(prefs::kDefaultContentSettings);
 
   if (overwrite)
     default_settings_.clear();
 
@@ skipping 66 matching lines @@
     SetWebsiteSetting(
         ContentSettingsPattern::Wildcard(),
         ContentSettingsPattern::Wildcard(),
         CONTENT_SETTINGS_TYPE_GEOLOCATION,
         std::string(),
         value->DeepCopy());
   }
 }
 
 }  // namespace content_settings