Add metrics for PasswordForm submission types

components/autofill/content/common/autofill_types.mojom

Index: components/autofill/content/common/autofill_types.mojom
diff --git a/components/autofill/content/common/autofill_types.mojom b/components/autofill/content/common/autofill_types.mojom
index 5e0c6ee9f3a6b6286d7ec98b32ae3598e3483762..f2a4a5ea92146dde9866e3e49427757c8974499c 100644
--- a/components/autofill/content/common/autofill_types.mojom
+++ b/components/autofill/content/common/autofill_types.mojom
@@ -52,6 +52,17 @@ enum PasswordFormScheme {
   SCHEME_USERNAME_ONLY
 };
 
+// autofill::PasswordForm::SubmissionEvent
+enum PasswordFormSubmissionEvent {
+    NONE,
+    HTML_FORM_SUBMISSION,
+    INPAGE_NAVIGATION,
+    XHR_SUCCEEDED,
+    FRAME_DETACHED,
+    BY_CONTEXT_MENU_CLICK,
+    SUBMISSION_EVENT_COUNT
+};
+
 // autofill::PasswordFormFieldPredictionType
 enum PasswordFormFieldPredictionType {
   PREDICTION_USERNAME,
@@ -182,6 +193,7 @@ struct PasswordForm {
   bool is_public_suffix_match;
   bool is_affiliation_based_match;
   bool does_look_like_signup_form;
+  PasswordFormSubmissionEvent submission_event;
 };
 
 // TODO(leonhsl): Use map directly after http://crbug.com/628104 solved.