Add "previewing on hover" support for single-field autocomplete input

components/autofill/core/browser/autofill_external_delegate.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/autofill/core/browser/autofill_external_delegate.h"
 
 #include "base/strings/utf_string_conversions.h"
 #include "components/autofill/core/browser/autocomplete_history_manager.h"
 #include "components/autofill/core/browser/autofill_driver.h"
 #include "components/autofill/core/browser/autofill_manager.h"
 #include "grit/component_strings.h"
 #include "third_party/WebKit/public/web/WebAutofillClient.h"
 #include "ui/base/l10n/l10n_util.h"
 
 using blink::WebAutofillClient;
+using base::ASCIIToUTF16;
 
 namespace autofill {
 
 AutofillExternalDelegate::AutofillExternalDelegate(
     AutofillManager* autofill_manager,
     AutofillDriver* autofill_driver)
     : autofill_manager_(autofill_manager),
       autofill_driver_(autofill_driver),
       password_autofill_manager_(autofill_driver),
       autofill_query_id_(0),
@@ skipping 139 matching lines @@
 }
 
 void AutofillExternalDelegate::DidSelectSuggestion(int identifier) {
   ClearPreviewedForm();
 
   // Only preview the data if it is a profile.
   if (identifier > 0)
     FillAutofillFormData(identifier, true);
 }
 
+void AutofillExternalDelegate::DidSelectAutocompleteSuggestion(
+    const base::string16& value) {
+  ClearPreviewedForm();
+  ClearAutocompletePreviewedField();
+
+  // Preview the data if it is in an AutoComplete field.
+  autofill_driver_->RendererShouldSetNodeText(value);

[Ilya Sherman, 2014/02/14 02:22:28]

This is incorrect.  The renderer should preview the text, not set it.  The
difference is essentially in whether the change is visible to JavaScript, though
this also makes it easier to restore the previous value prior to mouse-hover.

+}
+
 void AutofillExternalDelegate::DidAcceptSuggestion(const base::string16& value,
                                                    int identifier) {
   if (identifier == WebAutofillClient::MenuItemIDAutofillOptions) {
     // User selected 'Autofill Options'.
     autofill_manager_->ShowAutofillSettings();
   } else if (identifier == WebAutofillClient::MenuItemIDClearForm) {
     // User selected 'Clear form'.
     autofill_driver_->RendererShouldClearFilledForm();
   } else if (identifier == WebAutofillClient::MenuItemIDPasswordEntry) {
     bool success = password_autofill_manager_.DidAcceptAutofillSuggestion(
@@ skipping 24 matching lines @@
 void AutofillExternalDelegate::DidEndTextFieldEditing() {
   autofill_manager_->delegate()->HideAutofillPopup();
 
   has_shown_autofill_popup_for_current_edit_ = false;
 }
 
 void AutofillExternalDelegate::ClearPreviewedForm() {
   autofill_driver_->RendererShouldClearPreviewedForm();
 }
 
+void AutofillExternalDelegate::ClearAutocompletePreviewedField() {
+  autofill_driver_->RendererShouldSetNodeText(ASCIIToUTF16(""));

[Ilya Sherman, 2014/02/14 02:22:28]

This is incorrect.  The field value shouldn't be cleared; it should return to
whatever it was prior to being previewed.

+}
+
 void AutofillExternalDelegate::Reset() {
   autofill_manager_->delegate()->HideAutofillPopup();
 
   password_autofill_manager_.Reset();
 }
 
 void AutofillExternalDelegate::AddPasswordFormMapping(
       const FormFieldData& username_field,
       const PasswordFormFillData& fill_data) {
   password_autofill_manager_.AddPasswordFormMapping(username_field, fill_data);
@@ skipping 120 matching lines @@
   // Set the values that all datalist elements share.
   autofill_icons->insert(autofill_icons->begin(),
                          data_list_values_.size(),
                          base::string16());
   autofill_unique_ids->insert(autofill_unique_ids->begin(),
                               data_list_values_.size(),
                               WebAutofillClient::MenuItemIDDataListEntry);
 }
 
 }  // namespace autofill