Add support for autofilling radio buttons and checkboxes.

chrome/browser/autofill/form_structure.h

Index: chrome/browser/autofill/form_structure.h
diff --git a/chrome/browser/autofill/form_structure.h b/chrome/browser/autofill/form_structure.h
index 45cf2bbcc365e51c6ed7d834dd741a4181d81d3c..6ac65c109126877d9458b35cde51441a5d8e3bc8 100644
--- a/chrome/browser/autofill/form_structure.h
+++ b/chrome/browser/autofill/form_structure.h
@@ -127,6 +127,7 @@ class FormStructure {
   const AutofillField* field(size_t index) const;
   AutofillField* field(size_t index);
   size_t field_count() const;
+  size_t checkable_field_count() const;
 
   // Returns the number of fields that are able to be autofilled.
   size_t autofill_count() const { return autofill_count_; }
@@ -192,6 +193,9 @@ class FormStructure {
   // A vector of all the input fields in the form.
   ScopedVector<AutofillField> fields_;
 
+  // The number of fields able to be checked.
+  size_t checkable_field_count_;
+
   // The names of the form input elements, that are part of the form signature.
   // The string starts with "&" and the names are also separated by the "&"
   // character. E.g.: "&form_input1_name&form_input2_name&...&form_inputN_name"