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

chrome/browser/content_settings/content_settings_pref_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_pref_provider.h"
 
 #include <map>
 #include <string>
 #include <utility>
 
@@ skipping 204 matching lines @@
                   ContentSettingsPattern(),
                   content_type,
                   std::string());
 }
 
 void PrefProvider::Observe(
     int type,
     const content::NotificationSource& source,
     const content::NotificationDetails& details) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK_EQ(type, chrome::NOTIFICATION_PREF_CHANGED);
+  DCHECK_EQ(prefs_, content::Source<PrefService>(source).ptr());
+  DCHECK_EQ(*content::Details<std::string>(details).ptr(),
+            std::string(prefs::kContentSettingsPatternPairs));
 
-  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::kContentSettingsPatternPairs) {
-      NOTREACHED() << "Unexpected preference observed";
-      return;
-    }
-    ReadContentSettingsFromPref(true);
+  ReadContentSettingsFromPref(true);
 
-    NotifyObservers(ContentSettingsPattern(),
-                    ContentSettingsPattern(),
-                    CONTENT_SETTINGS_TYPE_DEFAULT,
-                    std::string());
-  } else {
-    NOTREACHED() << "Unexpected notification";
-  }
+  NotifyObservers(ContentSettingsPattern(),
+                  ContentSettingsPattern(),
+                  CONTENT_SETTINGS_TYPE_DEFAULT,
+                  std::string());
 }
 
 PrefProvider::~PrefProvider() {
   DCHECK(!prefs_);
 }
 
 RuleIterator* PrefProvider::GetRuleIterator(
     ContentSettingsType content_type,
     const ResourceIdentifier& resource_identifier,
     bool incognito) const {
@@ skipping 445 matching lines @@
 
 void PrefProvider::AssertLockNotHeld() const {
 #if !defined(NDEBUG)
   // |Lock::Acquire()| will assert if the lock is held by this thread.
   lock_.Acquire();
   lock_.Release();
 #endif
 }
 
 }  // namespace content_settings