[FragmentItem] Check CullRect in NGBoxFragmentPainter

This patch adds checking CullRect in |NGBoxFragmentPainter|.

The logic is the same as |NGPaintFragment| versions of the
corresponding functions.

Bug: 982194
Change-Id: Iaf1c7bdf9ac04ced4a772ee04f2f8497e1cb8911
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2145522Reviewed-by: Ian Kilpatrick <ikilpatrick@chromium.org>
Commit-Queue: Koji Ishii <kojii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#758746}

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

@@ -1433,6 +1433,13 @@ void NGBoxFragmentPainter::PaintTextItem(const NGInlineCursor& cursor,
       paint_info.phase != PaintPhase::kMask)
     return;
 
+  // Skip if this child does not intersect with CullRect.
+  if (!paint_info.IntersectsCullRect(
+          item.InkOverflow(), paint_offset + item.OffsetInContainerBlock()) &&
+      // Don't skip <br>, it doesn't have ink but need to paint selection.
+      !item.IsLineBreak())
+    return;
+
   NGTextFragmentPainter<NGInlineCursor> text_painter(cursor, parent_offset);
   text_painter.Paint(paint_info, paint_offset);
 }
@@ -1451,7 +1458,10 @@ void NGBoxFragmentPainter::PaintBoxItem(
   if (child_fragment.HasSelfPaintingLayer() || child_fragment.IsFloating())
     return;
 
-  // TODO(kojii): Check CullRect.
+  // Skip if this child does not intersect with CullRect.
+  if (!paint_info.IntersectsCullRect(
+          item.InkOverflow(), paint_offset + item.OffsetInContainerBlock()))
+    return;
 
   if (child_fragment.IsAtomicInline() || child_fragment.IsListMarker()) {
     if (FragmentRequiresLegacyFallback(child_fragment)) {
@@ -1480,6 +1490,11 @@ void NGBoxFragmentPainter::PaintBoxItem(const NGFragmentItem& item,
     return;
   }
 
+  // Skip if this child does not intersect with CullRect.
+  if (!paint_info.IntersectsCullRect(
+          item.InkOverflow(), paint_offset + item.OffsetInContainerBlock()))
+    return;
+
   // This |item| is a culled inline box.
   DCHECK(item.GetLayoutObject()->IsLayoutInline());
   NGInlineCursor children = cursor.CursorForDescendants();