Bug 1447166 part 1 - [css-grid] Make FindUsedFlexFraction iterate the GridItemInfo array instead of using a CSSOrderAwareFrameIterator (idempotent change). r=dholbert

layout/generic/nsGridContainerFrame.cpp

@@ -4581,12 +4581,9 @@ nsGridContainerFrame::Tracks::FindUsedFlexFraction(
   }
   WritingMode wm = aState.mWM;
   gfxContext* rc = &aState.mRenderingContext;
-  CSSOrderAwareFrameIterator& iter = aState.mIter;
-  iter.Reset();
   // ... the result of 'finding the size of an fr' for each item that spans
   // a flex track with its max-content contribution as 'space to fill'
-  for (; !iter.AtEnd(); iter.Next()) {
-    const GridItemInfo& item = aGridItems[iter.ItemIndex()];
+  for (const GridItemInfo& item : aGridItems) {
     if (item.mState[mAxis] & ItemState::eIsFlexing) {
       // XXX optimize: bug 1194446
       auto pb = Some(aState.PercentageBasisFor(mAxis, item));