Show display warning if the form is autocomplete off.

chrome/renderer/autofill/autofill_agent.cc

Index: chrome/renderer/autofill/autofill_agent.cc
diff --git a/chrome/renderer/autofill/autofill_agent.cc b/chrome/renderer/autofill/autofill_agent.cc
index 72110d0e41d54f1471a36c24144eaf555e7287ba..17d7a0c7c2daa5d1d7fdfa01f5cbba0266d8bc5e 100644
--- a/chrome/renderer/autofill/autofill_agent.cc
+++ b/chrome/renderer/autofill/autofill_agent.cc
@@ -234,7 +234,13 @@ void AutofillAgent::OnSuggestionsReturned(int query_id,
   std::vector<int> ids(unique_ids);
   int separator_index = -1;
 
-  if (ids[0] < 0 && ids.size() > 1) {
+  if (!autofill_query_node_.isNull() && !autofill_query_node_.autoComplete()) {
+    // If autofill is disabled and we had suggestions, show a warning instead.
+    v.assign(1, l10n_util::GetStringUTF16(IDS_AUTOFILL_WARNING_FORM_DISABLED));
+    l.assign(1, string16());
+    i.assign(1, string16());
+    ids.assign(1, -1);
+  } else if (ids[0] < 0 && ids.size() > 1) {
     // If we received a warning instead of suggestions from autofill but regular
     // suggestions from autocomplete, don't show the autofill warning.
     v.erase(v.begin());
@@ -320,7 +326,14 @@ void AutofillAgent::ShowSuggestions(const WebInputElement& element,
                                     bool autofill_on_empty_values,
                                     bool requires_caret_at_end,
                                     bool display_warning_if_disabled) {
-  if (!element.isEnabled() || element.isReadOnly() || !element.autoComplete() ||
+  // If autocomplete is disabled at the form level, then we might want to show
+  // a warning in place of suggestions. However, if autocomplete is disabled
+  // specifically for this field, we never want to show a warning. Otherwise,
+  // we might interfere with custom popups (e.g. search suggestions) used by
+  // the website.
+  const WebFormElement form = element.form();
+  if (!element.isEnabled() || element.isReadOnly() ||
+      (!element.autoComplete() && form.autoComplete()) ||
       !element.isTextField() || element.isPasswordField() ||
       !element.suggestedValue().isEmpty())
     return;
@@ -345,21 +358,21 @@ void AutofillAgent::ShowSuggestions(const WebInputElement& element,
   QueryAutofillSuggestions(element, display_warning_if_disabled);
 }
 
-void AutofillAgent::QueryAutofillSuggestions(const WebNode& node,
+void AutofillAgent::QueryAutofillSuggestions(const WebInputElement& element,
                                              bool display_warning_if_disabled) {
   static int query_counter = 0;
   autofill_query_id_ = query_counter++;
-  autofill_query_node_ = node;
+  autofill_query_node_ = element;
   display_warning_if_disabled_ = display_warning_if_disabled;
 
   webkit_glue::FormData form;
   webkit_glue::FormField field;
-  if (!FindFormAndFieldForNode(node, &form, &field)) {
+  if (!FindFormAndFieldForNode(element, &form, &field)) {
     // If we didn't find the cached form, at least let autocomplete have a shot
     // at providing suggestions.
-    FormManager::WebFormControlElementToFormField(
-        node.toConst<WebFormControlElement>(), FormManager::EXTRACT_VALUE,
-        &field);
+    FormManager::WebFormControlElementToFormField(element,
+                                                  FormManager::EXTRACT_VALUE,
+                                                  &field);
   }
 
   Send(new AutofillHostMsg_QueryFormFieldAutofill(