Bug 161452 Tree content and builder views may need to recheck empty status after children are removed based on patch by kyle yuan r=varga sr=bryner

content/xul/templates/src/nsTreeRows.h

@@ -388,12 +388,13 @@ public:
     /**
      * Remove the specified row from the view
      */
-    void
+    PRInt32
     RemoveRowAt(iterator& aIterator) {
-        iterator temp = aIterator++;
+        iterator temp = aIterator--;
         Subtree* parent = temp.GetParent();
         parent->RemoveRowAt(temp.GetChildIndex());
-        InvalidateCachedRow(); }
+        InvalidateCachedRow();
+        return parent->Count(); }
 
     /**
      * Insert a new match into the view

content/xul/templates/src/nsXULContentBuilder.cpp

@@ -1705,7 +1705,7 @@ nsXULContentBuilder::ReplaceMatch(nsIRDFResource* aMember,
 
         RemoveMember(content, member, PR_TRUE);
 
-        if (aNewMatch) {
+        if (!aNewMatch) {
             // If there's no new match, then go ahead an update the
             // container attributes now.
             SetContainerAttrs(content, aOldMatch);

content/xul/templates/src/nsXULTreeBuilder.cpp

@@ -1113,11 +1113,12 @@ nsXULTreeBuilder::ReplaceMatch(nsIRDFResource* aMember,
             // Remove the rows from the view
             PRInt32 row = iter.GetRowIndex();
             PRInt32 delta = mRows.GetSubtreeSizeFor(iter);
-            mRows.RemoveRowAt(iter);
-
-            // XXX Could potentially invalidate the iterator's
-            // mContainer[Type|State] caching here, but it'll work
-            // itself out.
+            if (mRows.RemoveRowAt(iter) == 0) {
+              // In this case iter now points to its parent
+              // Invalidate the row's cached fill state
+              iter->mContainerFill = nsTreeRows::eContainerFill_Unknown;
+              mBoxObject->InvalidatePrimaryCell(iter.GetRowIndex());
+            }
 
             // Notify the box object
             mBoxObject->RowCountChanged(row, -delta - 1);