Don't post tasks from RulesRegistry c-tor

chrome/browser/extensions/api/declarative/rules_registry.cc

Index: chrome/browser/extensions/api/declarative/rules_registry.cc
diff --git a/chrome/browser/extensions/api/declarative/rules_registry.cc b/chrome/browser/extensions/api/declarative/rules_registry.cc
index c9db12e78b88ea960e64bdf83e0acc861788ac98..3be5247b1ebd122c7638b39b543bb3fc6d0ab460 100644
--- a/chrome/browser/extensions/api/declarative/rules_registry.cc
+++ b/chrome/browser/extensions/api/declarative/rules_registry.cc
@@ -88,12 +88,10 @@ RulesRegistry::RulesRegistry(
   if (cache_delegate) {
     cache_delegate_ = cache_delegate->GetWeakPtr();
     cache_delegate->Init(this);
-  } else {
-    content::BrowserThread::PostTask(
-        owner_thread,
-        FROM_HERE,
-        base::Bind(&RulesRegistry::MarkReady, this, base::Time::Now()));
   }
+  // Note that if |cache_delegate| is NULL, the Rulesregistry never signals its
+  // |ready_| event. That's OK, because that event is only ever needed by the
+  // cache delegate.
 }
 
 std::string RulesRegistry::AddRulesNoFill(