Slightly upgrade decideRoleFromSibling() in AXTableCell

Source/modules/accessibility/AXTableCell.cpp

 /*
  * Copyright (C) 2008 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 90 matching lines @@
 
 bool AXTableCell::isTableCell() const
 {
     AXObject* parent = parentObjectUnignored();
     if (!parent || !parent->isTableRow())
         return false;
 
     return true;
 }
 
-static AccessibilityRole decideRoleFromSibling(Node* siblingNode)
+static AccessibilityRole decideRoleFromSibling(LayoutTableCell* siblingCell)
 {
-    if (!siblingNode)
+    if (!siblingCell)
         return CellRole;
-    if (siblingNode->hasTagName(thTag))
-        return ColumnHeaderRole;
-    if (siblingNode->hasTagName(tdTag))
-        return RowHeaderRole;
+
+    if (Node* siblingNode = siblingCell->node()) {
+        if (siblingNode->hasTagName(thTag))
+            return ColumnHeaderRole;
+        if (siblingNode->hasTagName(tdTag))
+            return RowHeaderRole;
+    }
+
     return CellRole;
 }
 
 AccessibilityRole AXTableCell::scanToDecideHeaderRole()
 {
     if (!isTableHeaderCell())
         return CellRole;
 
     // Check scope attribute first.
     if (isRowHeaderCell())
         return RowHeaderRole;
 
     if (isColumnHeaderCell())
         return ColumnHeaderRole;
 
     // Check the previous cell and the next cell on the same row.
     LayoutTableCell* layoutCell = toLayoutTableCell(m_layoutObject);
     AccessibilityRole headerRole = CellRole;
 
     // if header is preceded by header cells on the same row, then it is a
     // column header. If it is preceded by other cells then it's a row header.
-    if (LayoutTableCell* cell = layoutCell->previousCell()) {
-        Node* siblingNode = cell->node();
-        headerRole = decideRoleFromSibling(siblingNode);
-        if (headerRole != CellRole)
-            return headerRole;
-    }
+    if ((headerRole = decideRoleFromSibling(layoutCell->previousCell())) != CellRole)
+        return headerRole;
+
     // if header is followed by header cells on the same row, then it is a
     // column header. If it is followed by other cells then it's a row header.
-    if (LayoutTableCell* cell = layoutCell->nextCell()) {
-        Node* siblingNode = cell->node();
-        headerRole = decideRoleFromSibling(siblingNode);
-        if (headerRole != CellRole)
-            return headerRole;
-    }
+    if ((headerRole = decideRoleFromSibling(layoutCell->nextCell())) != CellRole)
+        return headerRole;
+
     // If there are no other cells on that row, then it is a column header.
     return ColumnHeaderRole;
 }
 
 AccessibilityRole AXTableCell::determineAccessibilityRole()
 {
     if (!isTableCell())
         return AXLayoutObject::determineAccessibilityRole();
 
     return scanToDecideHeaderRole();
@@ skipping 87 matching lines @@
         return 0;
 
     Node* cellElement = headerCell->node();
     if (!cellElement || !cellElement->hasTagName(thTag))
         return 0;
 
     return axObjectCache()->getOrCreate(headerCell);
 }
 
 } // namespace blink