iOS full-form Autofill: Handle partially filled forms correctly.

components/autofill/ios/browser/resources/autofill_controller.js

 // 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.
 
 // Installs Autofill management functions on the |__gCrWeb| object.
 //
 // It scans the DOM, extracting and storing forms and returns a JSON string
 // representing an array of objects, each of which represents an Autofill form
 // with information about a form to be filled and/or submitted and it can be
 // translated to struct FormData
@@ skipping 483 matching lines @@
     return;
   }
   __gCrWeb.autofill.lastAutoFilledElement = activeElement;
   __gCrWeb.autofill.fillFormField(data, activeElement);
 };
 
 /**
  * Fills a number of fields in the same named form.
  *
  * @param {Object<AutofillFormData>} data The data to fill in.
+ * @param {boolean} onlyFillEmpty Only fill empty fields. Otherwise fill all
+ *     fields.
+ * @param {string} forceFillFieldName Named field will always be filled,
+ *     regardless of value of |onlyFillEmpty|. May be null.
  * @param {boolean} styleElements Apply Autofill CSS style to filled elements.
  */
-__gCrWeb.autofill['fillForm'] = function(data, styleElements) {
+__gCrWeb.autofill['fillForm'] = function(data, onlyFillEmpty,
+    forceFillFieldName, styleElements) {
   // Inject CSS to style the autofilled elements with a yellow background.
   if (styleElements && !__gCrWeb.autofill.styleInjected) {
     var style = document.createElement('style');
     style.textContent = '[chrome-autofilled] {' +
       'background-color:#FAFFBD !important;' +
       'background-image:none !important;' +
       'color:#000000 !important;' +
       '}';
     document.head.appendChild(style);
     __gCrWeb.autofill.styleInjected = true;
   }
 
   // Remove Autofill styling when control element is edited.
   var controlElementInputListener = function(evt) {
     evt.target.removeAttribute('chrome-autofilled');
+    evt.target.isAutofilled = false;
     evt.target.removeEventListener('input', controlElementInputListener);
   };
 
   var form = __gCrWeb.common.getFormElementFromIdentifier(data.formName);
   var controlElements = __gCrWeb.common.getFormControlElements(form);
   for (var i = 0; i < controlElements.length; ++i) {
     var element = controlElements[i];
     if (!__gCrWeb.autofill.isAutofillableElement(element)) {
       continue;
     }
-    var value = data.fields[__gCrWeb['common'].nameForAutofill(element)];
+    var fieldName = __gCrWeb['common'].nameForAutofill(element);
+
+    // If directed, skip non-empty fields unless this is the forceFillFieldName
+    // or it's a 'select-one' element. 'select-one' elements are always
+    // autofilled even if non-empty; see
+    // AutofillManager::FillOrPreviewDataModelForm().
+    if (onlyFillEmpty && element.value && element.value.length > 0 &&
+        !__gCrWeb.autofill.isSelectElement(element) &&
+        fieldName !== forceFillFieldName) {
+      continue;
+    }
+    var value = data.fields[fieldName];
     if (value) {
       element.value = value;
       if (styleElements) {
         element.setAttribute('chrome-autofilled');
+        element.isAutofilled = true;
         element.addEventListener('input', controlElementInputListener);
       }
     }
   }
 
   // Remove Autofill styling when form receives 'reset' event.
   // Individual control elements may be left with 'input' event listeners but
   // they are harmless.
   if (styleElements) {
     var formResetListener = function(evt) {
       var controlElements = __gCrWeb.common.getFormControlElements(evt.target);
       for (var i = 0; i < controlElements.length; ++i) {
         controlElements[i].removeAttribute('chrome-autofilled');
+        controlElements[i].isAutofilled = false;
       }
       evt.target.removeEventListener('reset', formResetListener);
     };
 
     form.addEventListener('reset', formResetListener);
   }
 };
 
 /**
  * Dispatch an autocomplete event to the named form.
@@ skipping 1186 matching lines @@
         continue;
       }
       var elementName = __gCrWeb['common'].nameForAutofill(element);
       var value = formData[elementName];
       if (value) {
         element.placeholder = value;
       }
     }
   }
 };