--- a/dom/base/nsRange.cpp
+++ b/dom/base/nsRange.cpp
@@ -1261,17 +1261,17 @@ nsRange::SetStartBefore(nsINode& aNode, 
   if (!nsContentUtils::LegacyIsCallerNativeCode() &&
       !nsContentUtils::CanCallerAccess(&aNode)) {
     aRv.Throw(NS_ERROR_DOM_SECURITY_ERR);
     return;
   }
 
   AutoInvalidateSelection atEndOfBlock(this);
   int32_t offset = -1;
-  nsINode* parent = GetParentAndOffsetBefore(&aNode, &offset);
+  nsINode* parent = GetContainerAndOffsetBefore(&aNode, &offset);
   aRv = SetStart(parent, offset);
 }
 
 NS_IMETHODIMP
 nsRange::SetStartBefore(nsIDOMNode* aSibling)
 {
   nsCOMPtr<nsINode> sibling = do_QueryInterface(aSibling);
   if (!sibling) {
@@ -1451,17 +1451,17 @@ nsRange::SetEndBefore(nsINode& aNode, Er
   if (!nsContentUtils::LegacyIsCallerNativeCode() &&
       !nsContentUtils::CanCallerAccess(&aNode)) {
     aRv.Throw(NS_ERROR_DOM_SECURITY_ERR);
     return;
   }
 
   AutoInvalidateSelection atEndOfBlock(this);
   int32_t offset = -1;
-  nsINode* parent = GetParentAndOffsetBefore(&aNode, &offset);
+  nsINode* parent = GetContainerAndOffsetBefore(&aNode, &offset);
   aRv = SetEnd(parent, offset);
 }
 
 NS_IMETHODIMP
 nsRange::SetEndBefore(nsIDOMNode* aSibling)
 {
   nsCOMPtr<nsINode> sibling = do_QueryInterface(aSibling);
   if (!sibling) {

--- a/dom/base/nsRange.h
+++ b/dom/base/nsRange.h
@@ -183,17 +183,17 @@ public:
     MOZ_ASSERT(aOffset);
     nsINode* parentNode = aNode->GetParentNode();
     *aOffset = parentNode ? parentNode->IndexOf(aNode) : -1;
     if (*aOffset >= 0) {
       (*aOffset)++;
     }
     return parentNode;
   }
-  static nsINode* GetParentAndOffsetBefore(nsINode* aNode, int32_t* aOffset)
+  static nsINode* GetContainerAndOffsetBefore(nsINode* aNode, int32_t* aOffset)
   {
     MOZ_ASSERT(aNode);
     MOZ_ASSERT(aOffset);
     nsINode* parentNode = aNode->GetParentNode();
     *aOffset = parentNode ? parentNode->IndexOf(aNode) : -1;
     return parentNode;
   }