Make ExtensionContentSettingsStore refcounted.

chrome/browser/extensions/extension_content_settings_store.cc

Index: chrome/browser/extensions/extension_content_settings_store.cc
diff --git a/chrome/browser/extensions/extension_content_settings_store.cc b/chrome/browser/extensions/extension_content_settings_store.cc
index d8617b61cf4836095392137570a571d6099a3bf1..b7c17b0884b32dafda873530ff96fc07b56ebed2 100644
--- a/chrome/browser/extensions/extension_content_settings_store.cc
+++ b/chrome/browser/extensions/extension_content_settings_store.cc
@@ -54,8 +54,6 @@ ExtensionContentSettingsStore::ExtensionContentSettingsStore() {
 }
 
 ExtensionContentSettingsStore::~ExtensionContentSettingsStore() {
-  DCHECK(OnCorrectThread());
-  NotifyOfDestruction();
   STLDeleteValues(&entries_);
 }
 
@@ -434,12 +432,6 @@ ExtensionContentSettingsStore::ContentSettingSpec::ContentSettingSpec(
       setting(setting) {
 }
 
-void ExtensionContentSettingsStore::NotifyOfDestruction() {
-  FOR_EACH_OBSERVER(ExtensionContentSettingsStore::Observer,
-                    observers_,
-                    OnDestruction());
-}
-
 void ExtensionContentSettingsStore::NotifyOfContentSettingChanged(
     const std::string& extension_id,
     bool incognito) {