Prospective fix for autofill crash

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 624 matching lines @@
   }
   return false;
 }
 
 }  // namespace
 
 const size_t kMaxParseableFields = 200;
 
 bool IsMonthInput(const WebInputElement* element) {
   CR_DEFINE_STATIC_LOCAL(WebString, kMonth, ("month"));
-  return element && element->formControlType() == kMonth;
+  return element && !element->isNull() && element->formControlType() == kMonth;
 }
 
 // All text fields, including password fields, should be extracted.
 bool IsTextInput(const WebInputElement* element) {
-  return element && element->isTextField();
+  return element && !element->isNull() && element->isTextField();
 }
 
 bool IsSelectElement(const WebFormControlElement& element) {
   // Static for improved performance.
   CR_DEFINE_STATIC_LOCAL(WebString, kSelectOne, ("select-one"));
-  return element.formControlType() == kSelectOne;
+  return !element.isNull() && element.formControlType() == kSelectOne;
 }
 
 bool IsTextAreaElement(const WebFormControlElement& element) {
   // Static for improved performance.
   CR_DEFINE_STATIC_LOCAL(WebString, kTextArea, ("textarea"));
-  return element.formControlType() == kTextArea;
+  return !element.isNull() && element.formControlType() == kTextArea;
 }
 
 bool IsCheckableElement(const WebInputElement* element) {
-  if (!element)
+  if (!element || element->isNull())
     return false;
 
   return element->isCheckbox() || element->isRadioButton();
 }
 
 bool IsAutofillableInputElement(const WebInputElement* element) {
   return IsTextInput(element) ||
          IsMonthInput(element) ||
          IsCheckableElement(element);
 }
@@ skipping 504 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