Refactor GuestViewContainer::AttachRequest to allow for other request types

content/renderer/browser_plugin/browser_plugin_manager.h

Index: content/renderer/browser_plugin/browser_plugin_manager.h
diff --git a/content/renderer/browser_plugin/browser_plugin_manager.h b/content/renderer/browser_plugin/browser_plugin_manager.h
index 23cde185ed399435a3df77f1aee20d31a0de9f5b..cedaa5f04f6d36aa6e3995058f5d7612c2f8a810 100644
--- a/content/renderer/browser_plugin/browser_plugin_manager.h
+++ b/content/renderer/browser_plugin/browser_plugin_manager.h
@@ -51,6 +51,9 @@ class CONTENT_EXPORT BrowserPluginManager
   void UpdateDeviceScaleFactor();
   void UpdateFocusState();
   RenderViewImpl* render_view() const { return render_view_.get(); }
+
+  // Returns a new instance ID to be used by BrowserPlugin. Instance IDs are
+  // unique per process.
   int GetNextInstanceID();
 
   // RenderViewObserver override. Call on render thread.
@@ -75,7 +78,6 @@ class CONTENT_EXPORT BrowserPluginManager
 
   // This map is keyed by guest instance IDs.
   IDMap<BrowserPlugin> instances_;
-  int current_instance_id_;
   base::WeakPtr<RenderViewImpl> render_view_;
 
   DISALLOW_COPY_AND_ASSIGN(BrowserPluginManager);