Backed out changeset 0e82a2a87b39 (bug 1594288) for causing build bustages in nsDocShell.cpp on a CLOSED TREE

docshell/base/nsDocShell.cpp

@@ -3178,6 +3178,62 @@ nsDocShell* nsDocShell::GetInProcessChildAt(int32_t aIndex) {
   return static_cast<nsDocShell*>(child);
 }
 
+NS_IMETHODIMP
+nsDocShell::FindChildWithName(const nsAString& aName, bool aRecurse,
+                              bool aSameType, nsIDocShellTreeItem* aRequestor,
+                              nsIDocShellTreeItem* aOriginalRequestor,
+                              nsIDocShellTreeItem** aResult) {
+  NS_ENSURE_ARG_POINTER(aResult);
+
+  // if we don't find one, we return NS_OK and a null result
+  *aResult = nullptr;
+
+  if (aName.IsEmpty()) {
+    return NS_OK;
+  }
+
+  nsTObserverArray<nsDocLoader*>::ForwardIterator iter(mChildList);
+  while (iter.HasMore()) {
+    nsCOMPtr<nsIDocShellTreeItem> child = do_QueryObject(iter.GetNext());
+    NS_ENSURE_TRUE(child, NS_ERROR_FAILURE);
+    int32_t childType = child->ItemType();
+
+    if (aSameType && (childType != mItemType)) {
+      continue;
+    }
+
+    bool childNameEquals = false;
+    child->NameEquals(aName, &childNameEquals);
+    if (childNameEquals && ItemIsActive(child) &&
+        CanAccessItem(child, aOriginalRequestor)) {
+      child.swap(*aResult);
+      break;
+    }
+
+    // Only ask it to check children if it is same type
+    if (childType != mItemType) {
+      continue;
+    }
+
+    // Only ask the child if it isn't the requestor
+    if (aRecurse && (aRequestor != child)) {
+      // See if child contains the shell with the given name
+#ifdef DEBUG
+      nsresult rv =
+#endif
+          child->FindChildWithName(aName, true, aSameType,
+                                   static_cast<nsIDocShellTreeItem*>(this),
+                                   aOriginalRequestor, aResult);
+      NS_ASSERTION(NS_SUCCEEDED(rv), "FindChildWithName should not fail here");
+      if (*aResult) {
+        // found it
+        return NS_OK;
+      }
+    }
+  }
+  return NS_OK;
+}
+
 NS_IMETHODIMP
 nsDocShell::AddChildSHEntry(nsISHEntry* aCloneRef, nsISHEntry* aNewEntry,
                             int32_t aChildOffset, uint32_t aLoadType,

docshell/base/nsIDocShellTreeItem.idl

@@ -153,6 +153,26 @@ interface nsIDocShellTreeItem : nsISupports
 	[binaryname(GetInProcessChildAt)]
 	nsIDocShellTreeItem getChildAt(in long index);
 
+	/*
+	Return the child DocShellTreeItem with the specified name.
+	aName - This is the name of the item that is trying to be found.
+	aRecurse - Is used to tell the function to recurse through children.
+		Note, recursion will only happen through items of the same type.
+	aSameType - If this is set only children of the same type will be returned.
+	aRequestor - This is the docshellTreeItem that is requesting the find.  This
+		parameter is used when recursion is being used to avoid searching the same
+		tree again when a child has asked a parent to search for children.
+	aOriginalRequestor - The original treeitem that made the request, if any.
+    	This is used to ensure that we don't run into cross-site issues.
+
+	Note the search is depth first when recursing.
+	*/
+	nsIDocShellTreeItem findChildWithName(in AString aName,
+	                                      in boolean aRecurse,
+	                                      in boolean aSameType,
+	                                      in nsIDocShellTreeItem aRequestor,
+	                                      in nsIDocShellTreeItem aOriginalRequestor);
+
   /**
    * BrowsingContext associated with the DocShell.
    */

toolkit/components/browser/nsWebBrowser.cpp

@@ -472,6 +472,17 @@ nsWebBrowser::GetInProcessChildAt(int32_t aIndex,
   return NS_ERROR_UNEXPECTED;
 }
 
+NS_IMETHODIMP
+nsWebBrowser::FindChildWithName(const nsAString& aName, bool aRecurse,
+                                bool aSameType, nsIDocShellTreeItem* aRequestor,
+                                nsIDocShellTreeItem* aOriginalRequestor,
+                                nsIDocShellTreeItem** aResult) {
+  NS_ENSURE_ARG_POINTER(aResult);
+
+  *aResult = nullptr;
+  return NS_OK;
+}
+
 //*****************************************************************************
 // nsWebBrowser::nsIWebNavigation
 //*****************************************************************************