Split Blacklist from ExtensionSystem.

extensions/browser/extension_system.h

Index: extensions/browser/extension_system.h
diff --git a/extensions/browser/extension_system.h b/extensions/browser/extension_system.h
index 07e1225b3bcada6b6be19dd35836e2524a4183d6..300e094ef2cb45c57582d76fbafec844fea3b250 100644
--- a/extensions/browser/extension_system.h
+++ b/extensions/browser/extension_system.h
@@ -29,7 +29,6 @@ class BrowserContext;
 
 namespace extensions {
 
-class Blacklist;
 class ContentVerifier;
 class DeclarativeUserScriptMaster;
 class ErrorConsole;
@@ -93,9 +92,6 @@ class ExtensionSystem : public KeyedService {
   // The EventRouter is created at startup.
   virtual EventRouter* event_router() = 0;
 
-  // The blacklist is created at startup.
-  virtual Blacklist* blacklist() = 0;
-
   // The ErrorConsole is created at startup.
   virtual ErrorConsole* error_console() = 0;