DataList UI (Chromium part)

chrome/renderer/autofill/autofill_agent.cc

 // Copyright (c) 2012 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 "chrome/renderer/autofill/autofill_agent.h"
 
 #include "base/bind.h"
 #include "base/message_loop.h"
 #include "base/time.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/common/autofill_messages.h"
 #include "chrome/common/chrome_constants.h"
 #include "chrome/renderer/autofill/form_autofill_util.h"
 #include "chrome/renderer/autofill/password_autofill_manager.h"
 #include "content/public/renderer/render_view.h"
 #include "grit/chromium_strings.h"
 #include "grit/generated_resources.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebRect.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebDocument.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebFormControlElement.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebFrame.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebInputEvent.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebNode.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebNodeCollection.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebOptionElement.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebView.h"
-#include "third_party/WebKit/Source/WebKit/chromium/public/platform/WebRect.h"
 #include "ui/base/keycodes/keyboard_codes.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "webkit/forms/form_data.h"
 #include "webkit/forms/form_data_predictions.h"
 #include "webkit/forms/form_field.h"
 #include "webkit/forms/password_form.h"
 
+using WebKit::WebAutofillClient;
 using WebKit::WebFormControlElement;
 using WebKit::WebFormElement;
 using WebKit::WebFrame;
 using WebKit::WebInputElement;
 using WebKit::WebKeyboardEvent;
 using WebKit::WebNode;
+using WebKit::WebNodeCollection;
+using WebKit::WebOptionElement;
 using WebKit::WebString;
 using webkit::forms::FormData;
 using webkit::forms::FormDataPredictions;
 
 namespace {
 
 // The size above which we stop triggering autofill for an input text field
 // (so to avoid sending long strings through IPC).
 const size_t kMaximumTextSizeForAutofill = 1000;
 
+void AppendDataListSuggestions(const WebKit::WebInputElement& element,
+                               std::vector<string16>* values,
+                               std::vector<string16>* labels,
+                               std::vector<string16>* icons,
+                               std::vector<int>* item_ids) {
+  WebNodeCollection options = element.dataListOptions();
+  if (options.isNull())
+    return;
+
+  for (WebOptionElement option = options.firstItem().to<WebOptionElement>();
+      !option.isNull(); option = options.nextItem().to<WebOptionElement>()) {
+    if (!StartsWith(option.value(), element.value(), false))
+      continue;

[Ilya Sherman, 2012/04/16 21:45:49]

nit: Please add a blank line after this line, for easier visual scanning.

[keishi, 2012/04/17 09:15:10]

Done.

+    values->push_back(option.value());
+    if (option.value() != option.label())
+      labels->push_back(option.label());
+    else
+      labels->push_back(string16());
+    icons->push_back(string16());
+    item_ids->push_back(WebAutofillClient::MenuItemIDDataListEntry);
+  }
+}
+
 }  // namespace
 
 namespace autofill {
 
 AutofillAgent::AutofillAgent(
     content::RenderView* render_view,
     PasswordAutofillManager* password_autofill_manager)
     : content::RenderViewObserver(render_view),
       password_autofill_manager_(password_autofill_manager),
       autofill_query_id_(0),
       autofill_action_(AUTOFILL_NONE),
       display_warning_if_disabled_(false),
       was_query_node_autofilled_(false),
-      suggestions_clear_index_(-1),
-      suggestions_options_index_(-1),
       has_shown_autofill_popup_for_current_edit_(false),
       ALLOW_THIS_IN_INITIALIZER_LIST(weak_ptr_factory_(this)) {
   render_view->GetWebView()->setAutofillClient(this);
 }
 
 AutofillAgent::~AutofillAgent() {}
 
 bool AutofillAgent::OnMessageReceived(const IPC::Message& message) {
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(AutofillAgent, message)
@@ skipping 66 matching lines @@
 
 bool AutofillAgent::InputElementLostFocus() {
   Send(new AutofillHostMsg_HideAutofillPopup(routing_id()));
 
   return false;
 }
 
 void AutofillAgent::didAcceptAutofillSuggestion(const WebNode& node,
                                                 const WebString& value,
                                                 const WebString& label,
-                                                int unique_id,
+                                                int item_id,
                                                 unsigned index) {
   if (password_autofill_manager_->DidAcceptAutofillSuggestion(node, value))
     return;
 
-  DCHECK(node == autofill_query_element_);
+  DCHECK(node == element_);
 
-  if (suggestions_options_index_ != -1 &&
-      index == static_cast<unsigned>(suggestions_options_index_)) {
-    // User selected 'Autofill Options'.
-    Send(new AutofillHostMsg_ShowAutofillDialog(routing_id()));
-  } else if (suggestions_clear_index_ != -1 &&
-             index == static_cast<unsigned>(suggestions_clear_index_)) {
-    // User selected 'Clear form'.
-    form_cache_.ClearFormWithElement(autofill_query_element_);
-  } else if (!unique_id) {
-    // User selected an Autocomplete entry, so we fill directly.
-    WebInputElement element = node.toConst<WebInputElement>();
-    SetNodeText(value, &element);
-  } else {
-    // Fill the values for the whole form.
-    FillAutofillFormData(node, unique_id, AUTOFILL_FILL);
+  switch (item_id) {
+    case WebAutofillClient::MenuItemIDWarningMessage:
+    case WebAutofillClient::MenuItemIDSeparator:
+      NOTREACHED();
+      break;
+    case WebAutofillClient::MenuItemIDAutofillOptions:
+      // User selected 'Autofill Options'.
+      Send(new AutofillHostMsg_ShowAutofillDialog(routing_id()));
+      break;
+    case WebAutofillClient::MenuItemIDClearForm:
+      // User selected 'Clear form'.
+      form_cache_.ClearFormWithElement(element_);
+      break;
+    case WebAutofillClient::MenuItemIDAutocompleteEntry:
+    case WebAutofillClient::MenuItemIDPasswordEntry:
+    case WebAutofillClient::MenuItemIDDataListEntry:
+      // User selected an Autocomplete or password or datalist entry, so we
+      // fill directly.
+      SetNodeText(value, &element_);
+      break;
+    default:
+      // A positive item_id is a unique id for an autofill (vs. autocomplete)
+      // suggestion.
+      DCHECK_GT(item_id, 0);
+      // Fill the values for the whole form.
+      FillAutofillFormData(node, item_id, AUTOFILL_FILL);
   }
-
-  suggestions_clear_index_ = -1;
-  suggestions_options_index_ = -1;
 }
 
 void AutofillAgent::didSelectAutofillSuggestion(const WebNode& node,
                                                 const WebString& value,
                                                 const WebString& label,
-                                                int unique_id) {
-  DCHECK_GE(unique_id, 0);
+                                                int item_id) {
   if (password_autofill_manager_->DidSelectAutofillSuggestion(node))
     return;
 
   didClearAutofillSelection(node);
-  FillAutofillFormData(node, unique_id, AUTOFILL_PREVIEW);
+
+  if (item_id > 0)
+    FillAutofillFormData(node, item_id, AUTOFILL_PREVIEW);
 }
 
 void AutofillAgent::didClearAutofillSelection(const WebNode& node) {
   if (password_autofill_manager_->DidClearAutofillSelection(node))
     return;
 
-  if (!autofill_query_element_.isNull() && node == autofill_query_element_) {
-    ClearPreviewedFormWithElement(autofill_query_element_,
-                                  was_query_node_autofilled_);
+  if (!element_.isNull() && node == element_) {
+    ClearPreviewedFormWithElement(element_, was_query_node_autofilled_);
   } else {
     // TODO(isherman): There seem to be rare cases where this code *is*
     // reachable: see [ http://crbug.com/96321#c6 ].  Ideally we would
     // understand those cases and fix the code to avoid them.  However, so far I
     // have been unable to reproduce such a case locally.  If you hit this
     // NOTREACHED(), please file a bug against me.
     NOTREACHED();
   }
 }
 
 void AutofillAgent::removeAutocompleteSuggestion(const WebString& name,
                                                  const WebString& value) {
-  // The index of clear & options will have shifted down.
-  if (suggestions_clear_index_ != -1)
-    suggestions_clear_index_--;
-  if (suggestions_options_index_ != -1)
-    suggestions_options_index_--;
-
   Send(new AutofillHostMsg_RemoveAutocompleteEntry(routing_id(), name, value));
 }
 
 void AutofillAgent::textFieldDidEndEditing(const WebInputElement& element) {
   password_autofill_manager_->TextFieldDidEndEditing(element);
   has_shown_autofill_popup_for_current_edit_ = false;
   Send(new AutofillHostMsg_DidEndTextFieldEditing(routing_id()));
 }
 
 void AutofillAgent::textFieldDidChange(const WebInputElement& element) {
   // We post a task for doing the Autofill as the caret position is not set
   // properly at this point (http://bugs.webkit.org/show_bug.cgi?id=16976) and
   // it is needed to trigger autofill.
   weak_ptr_factory_.InvalidateWeakPtrs();
   MessageLoop::current()->PostTask(
         FROM_HERE,
         base::Bind(&AutofillAgent::TextFieldDidChangeImpl,
                    weak_ptr_factory_.GetWeakPtr(), element));
 }
 
 void AutofillAgent::TextFieldDidChangeImpl(const WebInputElement& element) {
   if (password_autofill_manager_->TextDidChangeInTextField(element)) {
-    autofill_query_element_ = element;
+    element_ = element;
     return;
   }
 
   ShowSuggestions(element, false, true, false);
 
   webkit::forms::FormData form;
   webkit::forms::FormField field;
   if (FindFormAndFieldForInputElement(element, &form, &field, REQUIRE_NONE)) {
     Send(new AutofillHostMsg_TextFieldDidChange(routing_id(), form, field,
                                                 base::TimeTicks::Now()));
   }
 }
 
 void AutofillAgent::textFieldDidReceiveKeyDown(const WebInputElement& element,
                                                const WebKeyboardEvent& event) {
   if (password_autofill_manager_->TextFieldHandlingKeyDown(element, event)) {
-    autofill_query_element_ = element;
+    element_ = element;
     return;
   }
 
   if (event.windowsKeyCode == ui::VKEY_DOWN ||
       event.windowsKeyCode == ui::VKEY_UP)
     ShowSuggestions(element, true, true, true);
 }
 
 void AutofillAgent::OnSuggestionsReturned(int query_id,
                                           const std::vector<string16>& values,
                                           const std::vector<string16>& labels,
                                           const std::vector<string16>& icons,
                                           const std::vector<int>& unique_ids) {
-  WebKit::WebView* web_view = render_view()->GetWebView();
-  if (!web_view || query_id != autofill_query_id_)
+  if (query_id != autofill_query_id_)
     return;
 
-  if (values.empty()) {
-    // No suggestions, any popup currently showing is obsolete.
-    web_view->hidePopups();
-    return;
-  }
-
   std::vector<string16> v(values);
   std::vector<string16> l(labels);
   std::vector<string16> i(icons);
   std::vector<int> ids(unique_ids);
-  int separator_index = -1;
 
-  DCHECK_GT(ids.size(), 0U);
-  if (!autofill_query_element_.isNull() &&
-      !autofill_query_element_.autoComplete()) {
+  // Only include "Autofill Options" special menu item if we have Autofill
+  // items, identified by |unique_ids| having at least one valid value.
+  bool has_autofill_item = false;
+  for (size_t j = 0; j < ids.size(); ++j) {
+    if (ids[j] > 0) {
+      has_autofill_item = true;
+      break;
+    }
+  }

[Ilya Sherman, 2012/04/16 21:45:49]

nit: It looks like you don't use |has_autofill_item| until further down in the
function.  If that's accurate, please restore this code's previous position, so
that it doesn't show up as a diff, since nothing has functionally changed.  In
either case, please restore the loop index to be |i| rather than |j|.

[keishi, 2012/04/17 09:15:10]

Done.

+
+  if (!element_.isNull() && !element_.autoComplete() && !v.empty()) {
     // 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.
+    ids.assign(1, WebAutofillClient::MenuItemIDWarningMessage);
+  } else if (ids.size() > 1 &&
+             ids[0] == WebAutofillClient::MenuItemIDWarningMessage) {
+    // If we received an autofill warning plus some autocomplete suggestions,
+    // remove the autofill warning.
     v.erase(v.begin());
     l.erase(l.begin());
     i.erase(i.begin());
     ids.erase(ids.begin());
   }
 
   // If we were about to show a warning and we shouldn't, don't.
-  if (ids[0] < 0 && !display_warning_if_disabled_)
-    return;
-
-  // Only include "Autofill Options" special menu item if we have Autofill
-  // items, identified by |unique_ids| having at least one valid value.
-  bool has_autofill_item = false;
-  for (size_t i = 0; i < ids.size(); ++i) {
-    if (ids[i] > 0) {
-      has_autofill_item = true;
-      break;
-    }
-  }
-
-  // The form has been auto-filled, so give the user the chance to clear the
-  // form.  Append the 'Clear form' menu item.
-  if (has_autofill_item &&
-      FormWithElementIsAutofilled(autofill_query_element_)) {
-    v.push_back(l10n_util::GetStringUTF16(IDS_AUTOFILL_CLEAR_FORM_MENU_ITEM));
-    l.push_back(string16());
-    i.push_back(string16());
-    ids.push_back(0);
-    suggestions_clear_index_ = v.size() - 1;
-    separator_index = v.size() - 1;
+  if (!display_warning_if_disabled_ && !v.empty() &&
+      ids[0] == WebAutofillClient::MenuItemIDWarningMessage) {
+    v.clear();
+    l.clear();
+    i.clear();
+    ids.clear();
   }
 
   if (has_autofill_item) {
+    v.push_back(string16());
+    l.push_back(string16());
+    i.push_back(string16());
+    ids.push_back(WebAutofillClient::MenuItemIDSeparator);
+
+    if (FormWithElementIsAutofilled(element_)) {
+      // The form has been auto-filled, so give the user the chance to clear the
+      // form.  Append the 'Clear form' menu item.
+      v.push_back(l10n_util::GetStringUTF16(IDS_AUTOFILL_CLEAR_FORM_MENU_ITEM));
+      l.push_back(string16());
+      i.push_back(string16());
+      ids.push_back(WebAutofillClient::MenuItemIDClearForm);
+    }
+
     // Append the 'Chrome Autofill options' menu item;
     v.push_back(l10n_util::GetStringUTF16(IDS_AUTOFILL_OPTIONS_POPUP));
     l.push_back(string16());
     i.push_back(string16());
-    ids.push_back(0);
-    suggestions_options_index_ = v.size() - 1;
-    separator_index = values.size();
+    ids.push_back(WebAutofillClient::MenuItemIDAutofillOptions);
+  }
+
+  if (!element_.isNull() && element_.isFocusable())

[Ilya Sherman, 2012/04/16 21:45:49]

nit: Can these checks be moved to the very top of the function, so that if they
fail, we just return early?  If so, you can also remove the element_.isNull()
check at line 313 (of this current Patch Set, #7 I think).

[keishi, 2012/04/17 09:15:10]

Done.

+    CombineDataListEntriesAndShow(element_, v, l, i, ids, has_autofill_item);
+}
+
+void AutofillAgent::CombineDataListEntriesAndShow(
+    const WebKit::WebInputElement& element,
+    const std::vector<string16>& values,
+    const std::vector<string16>& labels,
+    const std::vector<string16>& icons,
+    const std::vector<int>& item_ids,
+    bool has_autofill_item) {
+  std::vector<string16> v;
+  std::vector<string16> l;
+  std::vector<string16> i;
+  std::vector<int> ids;
+
+  AppendDataListSuggestions(element, &v, &l, &i, &ids);
+
+  // If there are both <datalist> items and Autofill suggestions, add a
+  // separator between them.
+  if (!v.empty() && !values.empty()) {
+    v.push_back(string16());
+    l.push_back(string16());
+    i.push_back(string16());
+    ids.push_back(WebAutofillClient::MenuItemIDSeparator);
+  }
+
+  v.insert(v.end(), values.begin(), values.end());
+  l.insert(l.end(), labels.begin(), labels.end());
+  i.insert(i.end(), icons.begin(), icons.end());
+  ids.insert(ids.end(), item_ids.begin(), item_ids.end());

[Ilya Sherman, 2012/04/16 21:45:49]

nit: Please add a brief comment for this block, something like "Append the
Autofill suggestions."

[keishi, 2012/04/17 09:15:10]

Done.

+
+  WebKit::WebView* web_view = render_view()->GetWebView();
+  if (!web_view)
+    return;
+
+  if (v.empty()) {
+    // No suggestions, any popup currently showing is obsolete.
+    web_view->hidePopups();
+    return;
   }
 
   // Send to WebKit for display.
-  if (!v.empty() && !autofill_query_element_.isNull() &&
-      autofill_query_element_.isFocusable()) {
-    web_view->applyAutofillSuggestions(
-        autofill_query_element_, v, l, i, ids, separator_index);
-  }
+  web_view->applyAutofillSuggestions(element, v, l, i, ids);
 
   Send(new AutofillHostMsg_DidShowAutofillSuggestions(
       routing_id(),
       has_autofill_item && !has_shown_autofill_popup_for_current_edit_));
   has_shown_autofill_popup_for_current_edit_ |= has_autofill_item;
 }
 
 void AutofillAgent::OnFormDataFilled(int query_id,
                                      const webkit::forms::FormData& form) {
   if (!render_view()->GetWebView() || query_id != autofill_query_id_)
     return;
 
-  was_query_node_autofilled_ = autofill_query_element_.isAutofilled();
+  was_query_node_autofilled_ = element_.isAutofilled();
 
   switch (autofill_action_) {
     case AUTOFILL_FILL:
-      FillForm(form, autofill_query_element_);
+      FillForm(form, element_);
       Send(new AutofillHostMsg_DidFillAutofillFormData(routing_id(),
                                                        base::TimeTicks::Now()));
       break;
     case AUTOFILL_PREVIEW:
-      didClearAutofillSelection(autofill_query_element_);
+      didClearAutofillSelection(element_);
 
-      PreviewForm(form, autofill_query_element_);
+      PreviewForm(form, element_);
       Send(new AutofillHostMsg_DidPreviewAutofillFormData(routing_id()));
       break;
     default:
       NOTREACHED();
   }
   autofill_action_ = AUTOFILL_NONE;
 }
 
 void AutofillAgent::OnFieldTypePredictionsAvailable(
     const std::vector<FormDataPredictions>& forms) {
   for (size_t i = 0; i < forms.size(); ++i) {
     form_cache_.ShowPredictions(forms[i]);
   }
 }
 
 void AutofillAgent::OnSelectAutofillSuggestionAtIndex(int listIndex) {
   NOTIMPLEMENTED();
   // TODO(jrg): enable once changes land in WebKit
   // render_view()->webview()->selectAutofillSuggestionAtIndex(listIndex);
 }
 
 void AutofillAgent::OnSetAutofillActionFill() {
   autofill_action_ = AUTOFILL_FILL;
 }
 
 void AutofillAgent::OnClearForm() {
-  form_cache_.ClearFormWithElement(autofill_query_element_);
+  form_cache_.ClearFormWithElement(element_);
 }
 
 void AutofillAgent::OnSetAutofillActionPreview() {
   autofill_action_ = AUTOFILL_PREVIEW;
 }
 
 void AutofillAgent::OnClearPreviewedForm() {
-  didClearAutofillSelection(autofill_query_element_);
+  didClearAutofillSelection(element_);
 }
 
 void AutofillAgent::OnSetNodeText(const string16& value) {
-  SetNodeText(value, &autofill_query_element_);
+  SetNodeText(value, &element_);
 }
 
 void AutofillAgent::OnAcceptPasswordAutofillSuggestion(const string16& value) {
   // We need to make sure this is handled here because the browser process
   // skipped it handling because it believed it would be handled here. If it
   // isn't handled here then the browser logic needs to be updated.
   bool handled = password_autofill_manager_->DidAcceptAutofillSuggestion(
-      autofill_query_element_,
+      element_,
       value);
   DCHECK(handled);
 }
 
 void AutofillAgent::ShowSuggestions(const WebInputElement& element,
                                     bool autofill_on_empty_values,
                                     bool requires_caret_at_end,
                                     bool display_warning_if_disabled) {
-  // 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.isNull() || form.autoComplete())) ||
-      !element.isTextField() || element.isPasswordField() ||
-      !element.suggestedValue().isEmpty())
-    return;
-
-  // If the field has no name, then we won't have values.
-  if (element.nameForAutofill().isEmpty())
+  if (!element.isEnabled() || element.isReadOnly() || !element.isTextField() ||
+      element.isPasswordField() || !element.suggestedValue().isEmpty())
     return;
 
   // Don't attempt to autofill with values that are too large or if filling
   // criteria are not met.
   WebString value = element.value();
   if (value.length() > kMaximumTextSizeForAutofill ||
       (!autofill_on_empty_values && value.isEmpty()) ||
       (requires_caret_at_end &&
        (element.selectionStart() != element.selectionEnd() ||
         element.selectionEnd() != static_cast<int>(value.length())))) {
     // Any popup currently showing is obsolete.
     WebKit::WebView* web_view = render_view()->GetWebView();
     if (web_view)
       web_view->hidePopups();
 
     return;
   }
 
+  element_ = element;
+
+  // 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. Also, if the field has no name, then we won't have values.
+  const WebFormElement form = element.form();
+  if ((!element.autoComplete() && (form.isNull() || form.autoComplete())) ||
+      element.nameForAutofill().isEmpty()) {
+    CombineDataListEntriesAndShow(element, std::vector<string16>(),
+                                  std::vector<string16>(),
+                                  std::vector<string16>(),
+                                  std::vector<int>(), false);
+    return;
+  }
+
   QueryAutofillSuggestions(element, display_warning_if_disabled);
 }
 
 void AutofillAgent::QueryAutofillSuggestions(const WebInputElement& element,
                                              bool display_warning_if_disabled) {
   static int query_counter = 0;
   autofill_query_id_ = query_counter++;
-  autofill_query_element_ = element;
   display_warning_if_disabled_ = display_warning_if_disabled;
 
   webkit::forms::FormData form;
   webkit::forms::FormField field;
   if (!FindFormAndFieldForInputElement(element, &form, &field,
                                        REQUIRE_AUTOCOMPLETE)) {
     // If we didn't find the cached form, at least let autocomplete have a shot
     // at providing suggestions.
     WebFormControlElementToFormField(element, EXTRACT_VALUE, &field);
   }
 
-  gfx::Rect bounding_box(autofill_query_element_.boundsInViewportSpace());
+  gfx::Rect bounding_box(element_.boundsInViewportSpace());
 
   Send(new AutofillHostMsg_QueryFormFieldAutofill(routing_id(),
                                                   autofill_query_id_,
                                                   form,
                                                   field,
                                                   bounding_box,
                                                   display_warning_if_disabled));
 }
 
 void AutofillAgent::FillAutofillFormData(const WebNode& node,
                                          int unique_id,
                                          AutofillAction action) {
+  DCHECK_GT(unique_id, 0);
+
   static int query_counter = 0;
   autofill_query_id_ = query_counter++;
 
   webkit::forms::FormData form;
   webkit::forms::FormField field;
   if (!FindFormAndFieldForInputElement(node.toConst<WebInputElement>(), &form,
                                        &field, REQUIRE_AUTOCOMPLETE)) {
     return;
   }
 
   autofill_action_ = action;
   Send(new AutofillHostMsg_FillAutofillFormData(
       routing_id(), autofill_query_id_, form, field, unique_id));
 }
 
 void AutofillAgent::SetNodeText(const string16& value,
                                 WebKit::WebInputElement* node) {
   string16 substring = value;
   substring = substring.substr(0, node->maxLength());
 
   node->setValue(substring, true);
 }
 
 }  // namespace autofill