When an element has multiple labels for Autofill, separate them with spaces.

chrome/renderer/autofill/form_manager.cc

 // Copyright (c) 2011 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/form_manager.h"
 
 #include "base/logging.h"
 #include "base/memory/scoped_vector.h"
 #include "base/stl_util.h"
 #include "base/string_util.h"
@@ skipping 746 matching lines @@
       element_name = label.getAttribute("for");
     } else if (
         !field_element.isFormControlElement() ||
         field_element.formControlType() == WebString::fromUTF8("hidden")) {
       continue;
     } else {
       element_name = field_element.nameForAutofill();
     }
 
     std::map<string16, FormField*>::iterator iter = name_map.find(element_name);
-    // Concatenate labels because some sites might have multiple label
-    // candidates.
-    if (iter != name_map.end())
-      iter->second->label += FindChildText(label);
+    if (iter != name_map.end()) {
+      string16 label_text = FindChildText(label);
+
+      // Concatenate labels because some sites might have multiple label
+      // candidates.
+      if (!iter->second->label.empty() && !label_text.empty())
+        iter->second->label += ASCIIToUTF16(" ");
+      iter->second->label += label_text;
+    }
   }
 
   // Loop through the form control elements, extracting the label text from
   // the DOM.  We use the |fields_extracted| vector to make sure we assign the
   // extracted label to the correct field, as it's possible |form_fields| will
   // not contain all of the elements in |control_elements|.
   for (size_t i = 0, field_idx = 0;
        i < control_elements.size() && field_idx < form_fields.size(); ++i) {
     // This field didn't meet the requirements, so don't try to find a label
     // for it.
@@ skipping 313 matching lines @@
     if (element_name == form.name && action == form.action) {
       *form_element = *form_iter;
       return true;
     }
   }
 
   return false;
 }
 
 }  // namespace autofill