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

chrome/browser/content_settings/cookie_settings.cc

Index: chrome/browser/content_settings/cookie_settings.cc
===================================================================
--- chrome/browser/content_settings/cookie_settings.cc	(revision 164413)
+++ chrome/browser/content_settings/cookie_settings.cc	(working copy)
@@ -159,20 +159,15 @@
                              const content::NotificationSource& source,
                              const content::NotificationDetails& details) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK_EQ(type, chrome::NOTIFICATION_PREF_CHANGED);
+  DCHECK_EQ(*content::Details<std::string>(details).ptr(),
+            std::string(prefs::kBlockThirdPartyCookies));
 
-  if (type == chrome::NOTIFICATION_PREF_CHANGED) {
-    PrefService* prefs = content::Source<PrefService>(source).ptr();
-    std::string* name = content::Details<std::string>(details).ptr();
-    if (*name == prefs::kBlockThirdPartyCookies) {
-      base::AutoLock auto_lock(lock_);
-      block_third_party_cookies_ = prefs->GetBoolean(
-          prefs::kBlockThirdPartyCookies);
-    } else {
-      NOTREACHED() << "Unexpected preference observed";
-      return;
-    }
-  } else {
-    NOTREACHED() << "Unexpected notification";
+  PrefService* prefs = content::Source<PrefService>(source).ptr();
+  {
+    base::AutoLock auto_lock(lock_);
+    block_third_party_cookies_ = prefs->GetBoolean(
+        prefs::kBlockThirdPartyCookies);
   }
 }