[LayoutNG] Fix incorrect DCHECK

Reduces crashes in the enabling CL[1].

[1] https://crrev.com/c/1719913

Bug: 988015
Change-Id: I78cbd3730957616ce5f70e9c69368a18b1d9d996
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1757965
Commit-Queue: Christian Biesinger <cbiesinger@chromium.org>
Reviewed-by: Christian Biesinger <cbiesinger@chromium.org>
Auto-Submit: Koji Ishii <kojii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#687693}

third_party/blink/renderer/core/paint/ng/ng_box_fragment_painter.h

@@ -187,14 +187,16 @@ inline NGBoxFragmentPainter::NGBoxFragmentPainter(
       paint_fragment_(paint_fragment) {
   DCHECK(box.IsBox() || box.IsRenderedLegend());
 #if DCHECK_IS_ON()
-  if (box.ChildrenInline() || box.IsInlineBox()) {
+  if ((box.ChildrenInline() && !box.Children().empty()) || box.IsInlineBox()) {
     DCHECK(paint_fragment);
     DCHECK_EQ(&paint_fragment->PhysicalFragment(), &box);
+  } else if (box.ChildrenInline() && box.Children().empty()) {
+    // If no children, there maybe or may not be NGPaintFragment.
+    // TODO(kojii): To be investigated if this correct or should be fixed.
   } else if (box.GetLayoutObject()->SlowFirstChild() &&
              box.GetLayoutObject()->SlowFirstChild()->IsLayoutFlowThread()) {
     // TODO(kojii): NGPaintFragment for multicol has non-inline children
     // (kColumnBox). Could this be regular box fragments?
-    DCHECK(paint_fragment);
   } else {
     DCHECK(!paint_fragment);
   }