Change event routers from singletons to being owned by the ExtensionService.

chrome/browser/extensions/extension_management_api.cc

Index: chrome/browser/extensions/extension_management_api.cc
diff --git a/chrome/browser/extensions/extension_management_api.cc b/chrome/browser/extensions/extension_management_api.cc
index 0053b1d3a48a60fea7835900faa2f0b9ed91cf00..73b905b0db856410fb4ca1d3ffa12008b5ded259 100644
--- a/chrome/browser/extensions/extension_management_api.cc
+++ b/chrome/browser/extensions/extension_management_api.cc
@@ -248,11 +248,6 @@ bool UninstallFunction::RunImpl() {
   return true;
 }
 
-// static
-ExtensionManagementEventRouter* ExtensionManagementEventRouter::GetInstance() {
-  return Singleton<ExtensionManagementEventRouter>::get();
-}
-
 ExtensionManagementEventRouter::ExtensionManagementEventRouter() {}
 
 ExtensionManagementEventRouter::~ExtensionManagementEventRouter() {}