Remove the unused parts of PPB_PDF

components/pdf/browser/pdf_web_contents_helper_client.h

Index: components/pdf/browser/pdf_web_contents_helper_client.h
diff --git a/components/pdf/browser/pdf_web_contents_helper_client.h b/components/pdf/browser/pdf_web_contents_helper_client.h
index 17dfb4ea06c770c87bb41dcb52d8157be860b3ff..eb983bf4f5dd83d39c11a70ebf9fcdc6cc12cb5c 100644
--- a/components/pdf/browser/pdf_web_contents_helper_client.h
+++ b/components/pdf/browser/pdf_web_contents_helper_client.h
@@ -15,10 +15,6 @@ class WebContents;
 
 namespace pdf {
 
-typedef base::Callback<
-    void(bool /* success */, const base::string16& /* password */)>
-    PasswordDialogClosedCallback;
-
 class PDFWebContentsHelperClient {
  public:
   virtual ~PDFWebContentsHelperClient() {}
@@ -31,11 +27,6 @@ class PDFWebContentsHelperClient {
   virtual void OnPDFHasUnsupportedFeature(content::WebContents* contents) = 0;
 
   virtual void OnSaveURL(content::WebContents* contents) = 0;
-
-  virtual void OnShowPDFPasswordDialog(
-      content::WebContents* contents,
-      const base::string16& prompt,
-      const PasswordDialogClosedCallback& callback) = 0;
 };
 
 }  // namespace pdf