[Password Manager] Use XHR completion as a possible signal for form submission

components/autofill/content/renderer/password_autofill_agent.h

Index: components/autofill/content/renderer/password_autofill_agent.h
diff --git a/components/autofill/content/renderer/password_autofill_agent.h b/components/autofill/content/renderer/password_autofill_agent.h
index f8f7d0ac4df3fe40327c7a50fbb63d38080f67c4..7bff47c3baf641c837ba711d095756f3654f5d4a 100644
--- a/components/autofill/content/renderer/password_autofill_agent.h
+++ b/components/autofill/content/renderer/password_autofill_agent.h
@@ -64,11 +64,15 @@ class PasswordAutofillAgent : public content::RenderFrameObserver {
   // Called when new form controls are inserted.
   void OnDynamicFormsSeen();
 
+  void OnFormElementsRemoved(const blink::WebVector<blink::WebNode>& nodes);
+
   // Called when the user first interacts with the page after a load. This is a
   // signal to make autofilled values of password input elements accessible to
   // JavaScript.
   void FirstUserGestureObserved();
 
+  void XHRSucceeded();
+
  protected:
   virtual bool OriginCanAccessPasswordManager(
       const blink::WebSecurityOrigin& origin);
@@ -226,6 +230,9 @@ class PasswordAutofillAgent : public content::RenderFrameObserver {
   void ProvisionallySavePassword(const blink::WebFormElement& form,
                                  ProvisionallySaveRestriction restriction);
 
+  // Returns true if
+  bool ProvisionallySavedPasswordIsValid();
+
   // Passes through |RenderViewObserver| method to |this|.
   LegacyPasswordAutofillAgent legacy_;