Add early return logic to LayoutNGBlockFlowMixin::NodeAtPoint

Following r813630 crrev.com/c/2448269 that added the early
return to |NGBoxFragmentPainter::NodeAtPoint|, this patch:
* Extracts more correct early return logic from |LayoutBox::
  HitTestAllPhases|. It looks like |LayoutNGBlockFlowMixin|
  copied from it in 2017 (r508056 crrev.com/c/710498), but
  the logic in |LayoutBox::HitTestAllPhases| evolved.
* Changes |IsScrollContainer| to
  |ShouldClipOverflowAlongBothAxis| because it misses
  other clipping situations.
* Changes to unite |PhysicalBorderBoxRect| and the overflow.
* Changes |LayoutNGBlockFlowMixin| to apply the early return
  logic not only when |NGPaintFragment|.

The early return in |LayoutNGBlockFlowMixin| improves the
perf test by ~65%, to almost equivalent to M85.

Note the previous patch (r813630) should match this, I will
do it in a following patch.

Bug: 1134574
Change-Id: If8e2fc5f52254168cd994c7fdf1d54aa5653da0c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2448709
Commit-Queue: Koji Ishii <kojii@chromium.org>
Reviewed-by: Xianzhu Wang <wangxianzhu@chromium.org>
Reviewed-by: Ian Kilpatrick <ikilpatrick@chromium.org>
Cr-Commit-Position: refs/heads/master@{#814225}

third_party/blink/renderer/core/layout/layout_box.cc

@@ -2238,30 +2238,38 @@ LayoutUnit LayoutBox::AdjustContentBoxLogicalHeightForBoxSizing(
 }
 
 // Hit Testing
-bool LayoutBox::HitTestAllPhases(HitTestResult& result,
-                                 const HitTestLocation& hit_test_location,
-                                 const PhysicalOffset& accumulated_offset,
-                                 HitTestFilter hit_test_filter) {
+bool LayoutBox::MayIntersect(const HitTestResult& result,
+                             const HitTestLocation& hit_test_location,
+                             const PhysicalOffset& accumulated_offset) const {
   NOT_DESTROYED();
   // Check if we need to do anything at all.
   // If we have clipping, then we can't have any spillout.
   // TODO(pdr): Why is this optimization not valid for the effective root?
-  if (!IsEffectiveRootScroller()) {
-    PhysicalRect overflow_box;
-    if (result.GetHitTestRequest().GetType() &
-        HitTestRequest::kHitTestVisualOverflow) {
-      overflow_box = PhysicalVisualOverflowRectIncludingFilters();
-    } else {
-      overflow_box = (IsScrollContainer() || ShouldApplyPaintContainment())
-                         ? PhysicalBorderBoxRect()
-                         : PhysicalVisualOverflowRect();
-    }
+  if (UNLIKELY(IsEffectiveRootScroller()))
+    return true;
 
-    PhysicalRect adjusted_overflow_box = overflow_box;
-    adjusted_overflow_box.Move(accumulated_offset);
-    if (!hit_test_location.Intersects(adjusted_overflow_box))
-      return false;
+  PhysicalRect overflow_box;
+  if (result.GetHitTestRequest().GetType() &
+      HitTestRequest::kHitTestVisualOverflow) {
+    overflow_box = PhysicalVisualOverflowRectIncludingFilters();
+  } else {
+    // Unite because overflow may not include borders.
+    overflow_box = PhysicalBorderBoxRect();
+    if (!ShouldClipOverflowAlongBothAxis() && HasVisualOverflow())
+      overflow_box.Unite(PhysicalVisualOverflowRect());
   }
+
+  overflow_box.Move(accumulated_offset);
+  return hit_test_location.Intersects(overflow_box);
+}
+
+bool LayoutBox::HitTestAllPhases(HitTestResult& result,
+                                 const HitTestLocation& hit_test_location,
+                                 const PhysicalOffset& accumulated_offset,
+                                 HitTestFilter hit_test_filter) {
+  NOT_DESTROYED();
+  if (!MayIntersect(result, hit_test_location, accumulated_offset))
+    return false;
   return LayoutObject::HitTestAllPhases(result, hit_test_location,
                                         accumulated_offset, hit_test_filter);
 }
@@ -2271,6 +2279,9 @@ bool LayoutBox::NodeAtPoint(HitTestResult& result,
                             const PhysicalOffset& accumulated_offset,
                             HitTestAction action) {
   NOT_DESTROYED();
+  if (!MayIntersect(result, hit_test_location, accumulated_offset))
+    return false;
+
   bool should_hit_test_self = IsInSelfHitTestingPhase(action);
 
   if (should_hit_test_self && IsScrollContainer() &&

third_party/blink/renderer/core/layout/layout_box.h

@@ -995,6 +995,10 @@ class CORE_EXPORT LayoutBox : public LayoutBoxModelObject {
                    const HitTestLocation&,
                    const PhysicalOffset& accumulated_offset,
                    HitTestAction) override;
+  // Fast check if |NodeAtPoint| may find a hit.
+  bool MayIntersect(const HitTestResult& result,
+                    const HitTestLocation& hit_test_location,
+                    const PhysicalOffset& accumulated_offset) const;
 
   // This function calculates the preferred widths for an object.
   //

third_party/blink/renderer/core/layout/ng/layout_ng_block_flow_mixin.cc

@@ -216,17 +216,10 @@ bool LayoutNGBlockFlowMixin<Base>::NodeAtPoint(
     const HitTestLocation& hit_test_location,
     const PhysicalOffset& accumulated_offset,
     HitTestAction action) {
+  if (!Base::MayIntersect(result, hit_test_location, accumulated_offset))
+    return false;
+
   if (const NGPaintFragment* paint_fragment = PaintFragment()) {
-    if (!Base::IsEffectiveRootScroller()) {
-      // Check if we need to do anything at all.
-      // If we have clipping, then we can't have any spillout.
-      PhysicalRect overflow_box = Base::IsScrollContainer()
-                                      ? Base::PhysicalBorderBoxRect()
-                                      : Base::PhysicalVisualOverflowRect();
-      overflow_box.Move(accumulated_offset);
-      if (!hit_test_location.Intersects(overflow_box))
-        return false;
-    }
     if (Base::IsInSelfHitTestingPhase(action) && Base::IsScrollContainer() &&
         Base::HitTestOverflowControl(result, hit_test_location,
                                      accumulated_offset))