Autofill: Consider placeholder text when inferring an input's label.

components/autofill/content/renderer/form_autofill_util.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/content/renderer/form_autofill_util.h"
 
 #include <map>
 
 #include "base/command_line.h"
 #include "base/logging.h"
@@ skipping 256 matching lines @@
       inferred_label = FindChildText(previous);
 
     break;
   }
 
   base::TrimWhitespace(inferred_label, base::TRIM_ALL, &inferred_label);
   return inferred_label;
 }
 
 // Helper for |InferLabelForElement()| that infers a label, if possible, from
+// placeholder text,
+base::string16 InferLabelFromPlaceholder(const WebFormControlElement& element) {
+  CR_DEFINE_STATIC_LOCAL(WebString, kPlaceholder, ("placeholder"));
+  if (element.hasAttribute(kPlaceholder))
+    return element.getAttribute(kPlaceholder);
+
+  return base::string16();
+}
+
+// Helper for |InferLabelForElement()| that infers a label, if possible, from
 // enclosing list item,
 // e.g. <li>Some Text<input ...><input ...><input ...></tr>
 base::string16 InferLabelFromListItem(const WebFormControlElement& element) {
   WebNode parent = element.parentNode();
   CR_DEFINE_STATIC_LOCAL(WebString, kListItem, ("li"));
   while (!parent.isNull() && parent.isElementNode() &&
          !parent.to<WebElement>().hasHTMLTagName(kListItem)) {
     parent = parent.parentNode();
   }
 
@@ skipping 127 matching lines @@
   return FindChildText(previous);
 }
 
 // Infers corresponding label for |element| from surrounding context in the DOM,
 // e.g. the contents of the preceding <p> tag or text element.
 base::string16 InferLabelForElement(const WebFormControlElement& element) {
   base::string16 inferred_label = InferLabelFromPrevious(element);
   if (!inferred_label.empty())
     return inferred_label;
 
+  // If we didn't find a label, check for placeholder text.
+  inferred_label = InferLabelFromPlaceholder(element);
+  if (!inferred_label.empty())
+    return inferred_label;
+
   // If we didn't find a label, check for list item case.
   inferred_label = InferLabelFromListItem(element);
   if (!inferred_label.empty())
     return inferred_label;
 
   // If we didn't find a label, check for table cell case.
   inferred_label = InferLabelFromTableColumn(element);
   if (!inferred_label.empty())
     return inferred_label;
 
@@ skipping 754 matching lines @@
 
 gfx::RectF GetScaledBoundingBox(float scale, WebFormControlElement* element) {
   gfx::Rect bounding_box(element->boundsInViewportSpace());
   return gfx::RectF(bounding_box.x() * scale,
                     bounding_box.y() * scale,
                     bounding_box.width() * scale,
                     bounding_box.height() * scale);
 }
 
 }  // namespace autofill