bc6443a9_lp____Extract_Interface_Dialog__Item
[Description] When this check box is cleared, PhpStorm just creates an interface in a separate file and marks the source class as implementation of the new interface. When the check box is selected, PhpStorm creates an interface and attempts to replace references to the source class with references to the interface in PhpDoc comments and parameters of methods. The proposed changes are compulsory displayed in a Refactoring Preview pane of the Find tool window. To have the interface extracted and the proposed changes applied, click Do Refactor. [Item] 
Replace class reference with interface where possible
PhpStorm 8.0.2 Help :: Extract Interface Dialog