Backed out changeset 90d627f2471e (bug 564979) because it broke mochitests.

content/base/public/nsINode.h

@@ -922,6 +922,15 @@ public:
   nsIContent* GetSelectionRootContent(nsIPresShell* aPresShell);
 
   virtual nsINodeList* GetChildNodesList();
+  nsIContent* GetSibling(PRInt32 aOffset)
+  {
+    nsINode *parent = GetNodeParent();
+    if (!parent) {
+      return nsnull;
+    }
+
+    return parent->GetChildAt(parent->IndexOf(this) + aOffset);
+  }
   nsIContent* GetFirstChild() const { return mFirstChild; }
   nsIContent* GetLastChild() const
   {

content/base/src/nsGenericElement.cpp

@@ -514,7 +514,7 @@ nsINode::GetPreviousSibling(nsIDOMNode** aPrevSibling)
 {
   *aPrevSibling = nsnull;
 
-  nsIContent *sibling = GetPreviousSibling();
+  nsIContent *sibling = GetSibling(-1);
 
   return sibling ? CallQueryInterface(sibling, aPrevSibling) : NS_OK;
 }
@@ -524,7 +524,7 @@ nsINode::GetNextSibling(nsIDOMNode** aNextSibling)
 {
   *aNextSibling = nsnull;
 
-  nsIContent *sibling = GetNextSibling();
+  nsIContent *sibling = GetSibling(1);
 
   return sibling ? CallQueryInterface(sibling, aNextSibling) : NS_OK;
 }

extensions/spellcheck/src/mozInlineSpellWordUtil.cpp

@@ -134,7 +134,6 @@ typedef void (* OnLeaveNodeFunPtr)(nsIDOMNode* aNode, void* aClosure);
 // Find the next node in the DOM tree in preorder. This isn't fast because
 // one call to GetNextSibling can be O(N) in the number of siblings...
 // Calls OnLeaveNodeFunPtr when the traversal leaves a node
-// XXXbz if this used nsINode, this would be trivial
 static nsIDOMNode*
 FindNextNode(nsIDOMNode* aNode, nsIDOMNode* aRoot,
              OnLeaveNodeFunPtr aOnLeaveNode = nsnull, void* aClosure = nsnull)
@@ -189,8 +188,7 @@ FindNextTextNode(nsIDOMNode* aNode, PRInt32 aOffset, nsIDOMNode* aRoot)
   } else {
     // aOffset was beyond the end of the child list. 
     // goto next node in a preorder DOM traversal.
-    // XXXbz this is generally reimplementing GetNextNode.
-    nsINode* next = node->GetNextSibling();
+    nsINode* next = node->GetSibling(1);
     if (!next) {
       nsCOMPtr<nsINode> root = do_QueryInterface(aRoot);
       while (!next) {
@@ -200,7 +198,7 @@ FindNextTextNode(nsIDOMNode* aNode, PRInt32 aOffset, nsIDOMNode* aRoot)
           return nsnull;
         }
         node = next;
-        next = node->GetNextSibling();
+        next = node->GetSibling(1);
       }
     }
     checkNode = do_QueryInterface(next);

js/src/xpconnect/src/dom_quickstubs.qsconf

@@ -565,12 +565,12 @@ CUSTOM_QS_TN = {
 customMethodCalls = {
     'nsIDOMNode_GetNextSibling': {
         'thisType': 'nsINode',
-        'code': '    nsINode *result = self->GetNextSibling();',
+        'code': '    nsINode *result = self->GetSibling(1);',
         'canFail': False
         },
     'nsIDOMNode_GetFirstChild': {
         'thisType': 'nsINode',
-        'code': '    nsINode *result = self->GetFirstChild();',
+        'code': '    nsINode *result = self->GetChildAt(0);',
         'canFail': False
         },
     'nsIDOMNode_GetChildNodes': {
@@ -579,7 +579,7 @@ customMethodCalls = {
         },
     'nsIDOMNode_GetPreviousSibling': {
         'thisType': 'nsINode',
-        'code': '    nsINode *result = self->GetPreviousSibling();',
+        'code': '    nsINode *result = self->GetSibling(-1);',
         'canFail': False
         },
     'nsIDOMNode_GetLastChild': {