Log observations of explicit UPI-VPA autocomplete hints.

components/autofill/core/browser/form_structure.h

Index: components/autofill/core/browser/form_structure.h
diff --git a/components/autofill/core/browser/form_structure.h b/components/autofill/core/browser/form_structure.h
index e984a5f1514a86057e894c0ef519bb716d186439..0047a3e55eda05ab987a26b68586fe7376b61b56 100644
--- a/components/autofill/core/browser/form_structure.h
+++ b/components/autofill/core/browser/form_structure.h
@@ -202,12 +202,18 @@ class FormStructure {
 
   const GURL& target_url() const { return target_url_; }
 
-  bool has_author_specified_types() { return has_author_specified_types_; }
+  bool has_author_specified_types() const {
+    return has_author_specified_types_;
+  }
 
-  bool has_author_specified_sections() {
+  bool has_author_specified_sections() const {
     return has_author_specified_sections_;
   }
 
+  bool has_author_specified_upi_vpa_hint() const {
+    return has_author_specified_upi_vpa_hint_;
+  }
+
   void set_upload_required(UploadRequired required) {
     upload_required_ = required;
   }
@@ -293,6 +299,10 @@ class FormStructure {
   // author, via the autocomplete attribute.
   bool has_author_specified_sections_;
 
+  // Whether the form includes a field that explicitly sets it autocomplete
+  // type to "upi-vpa".
+  bool has_author_specified_upi_vpa_hint_;
+
   // Whether the form was parsed for autocomplete attribute, thus assigning
   // the real values of |has_author_specified_types_| and
   // |has_author_specified_sections_|.