content/browser: Move notification_service_impl into content namespace.

content/public/test/test_content_client_initializer.h

Index: content/public/test/test_content_client_initializer.h
diff --git a/content/public/test/test_content_client_initializer.h b/content/public/test/test_content_client_initializer.h
index 9bb1ffe3087d27a4b36fea8ad029ac3b7a188af5..71e2918bd2c13c12b21367c4c5b44c302f5da9b1 100644
--- a/content/public/test/test_content_client_initializer.h
+++ b/content/public/test/test_content_client_initializer.h
@@ -8,12 +8,11 @@
 #include "base/basictypes.h"
 #include "base/memory/scoped_ptr.h"
 
-class NotificationServiceImpl;
-
 namespace content {
 
 class ContentClient;
 class MockRenderProcessHostFactory;
+class NotificationServiceImpl;
 class TestContentBrowserClient;
 class TestRenderViewHostFactory;