Move ExtensionHost into extensions namespace

chrome/browser/extensions/extension_infobar_delegate.h

Index: chrome/browser/extensions/extension_infobar_delegate.h
diff --git a/chrome/browser/extensions/extension_infobar_delegate.h b/chrome/browser/extensions/extension_infobar_delegate.h
index 76d997cf90732012a89c185c5c26840ce913ef79..ad204681f08359f8987ab5ddc2de1c87e4025724 100644
--- a/chrome/browser/extensions/extension_infobar_delegate.h
+++ b/chrome/browser/extensions/extension_infobar_delegate.h
@@ -11,11 +11,11 @@
 #include "content/public/browser/notification_registrar.h"
 
 class Browser;
-class ExtensionHost;
 class GURL;
 
 namespace extensions {
 class Extension;
+class ExtensionHost;
 }
 
 // The InfobarDelegate for creating and managing state for the ExtensionInfobar
@@ -39,7 +39,7 @@ class ExtensionInfoBarDelegate : public InfoBarDelegate,
                            int height);
 
   const extensions::Extension* extension() { return extension_; }
-  ExtensionHost* extension_host() { return extension_host_.get(); }
+  extensions::ExtensionHost* extension_host() { return extension_host_.get(); }
   int height() { return height_; }
 
   void set_observer(DelegateObserver* observer) { observer_ = observer; }
@@ -67,7 +67,7 @@ class ExtensionInfoBarDelegate : public InfoBarDelegate,
   // own this since the InfoBar gets deleted and recreated when you switch tabs
   // and come back (and we don't want the user's interaction with the InfoBar to
   // get lost at that point).
-  scoped_ptr<ExtensionHost> extension_host_;
+  scoped_ptr<extensions::ExtensionHost> extension_host_;
 
   // The observer monitoring when the delegate dies.
   DelegateObserver* observer_;