Enable accessible name of a control to include multiple <label> elements.

third_party/WebKit/Source/modules/accessibility/AXLayoutObject.cpp

Index: third_party/WebKit/Source/modules/accessibility/AXLayoutObject.cpp
diff --git a/third_party/WebKit/Source/modules/accessibility/AXLayoutObject.cpp b/third_party/WebKit/Source/modules/accessibility/AXLayoutObject.cpp
index 42cdc55a52f5ab4aa4dad3334dbbf5b6c9762e88..1d124aab0e27085b4698bfe0d321f07fc8ca6a96 100644
--- a/third_party/WebKit/Source/modules/accessibility/AXLayoutObject.cpp
+++ b/third_party/WebKit/Source/modules/accessibility/AXLayoutObject.cpp
@@ -52,6 +52,7 @@
 #include "core/html/HTMLOptionElement.h"
 #include "core/html/HTMLSelectElement.h"
 #include "core/html/HTMLTextAreaElement.h"
+#include "core/html/LabelsNodeList.h"
 #include "core/html/shadow/ShadowElementNames.h"
 #include "core/layout/HitTestResult.h"
 #include "core/layout/LayoutFileUploadControl.h"
@@ -2468,12 +2469,17 @@ LayoutRect AXLayoutObject::computeElementRect() const
     if (isWebArea() && obj->frame()->view())
         result.setSize(LayoutSize(obj->frame()->view()->contentsSize()));
 
-    // Checkboxes and radio buttons include their label as part of their rect.
-    if (isCheckboxOrRadio()) {
-        HTMLLabelElement* label = labelForElement(toElement(m_layoutObject->node()));
-        if (label && label->layoutObject()) {
-            LayoutRect labelRect = axObjectCache().getOrCreate(label)->elementRect();
-            result.unite(labelRect);
+    // Checkboxes and radio buttons include their labels as part of their rect.
+    if (isCheckboxOrRadio() && isLabelableElement(obj->node())) {
+        LabelsNodeList* labels = toLabelableElement(obj->node())->labels();
+        if (labels) {
+            for (unsigned labelIndex = 0; labelIndex < labels->length(); ++labelIndex) {
+                AXObject* labelAXObject = axObjectCache().getOrCreate(labels->item(labelIndex));
+                if (labelAXObject) {
+                    LayoutRect labelRect = labelAXObject->elementRect();
+                    result.unite(labelRect);
+                }
+            }
         }
     }