Use floating_object's parent object to check for overhanging floats.

third_party/WebKit/Source/core/layout/LayoutBlockFlow.cpp

Index: third_party/WebKit/Source/core/layout/LayoutBlockFlow.cpp
diff --git a/third_party/WebKit/Source/core/layout/LayoutBlockFlow.cpp b/third_party/WebKit/Source/core/layout/LayoutBlockFlow.cpp
index 6c63e3e501bae956eefcec22ad1d4cff3840b2d8..c8b74c6cdc332c6ddf1eed63625e5fe44dd2d872 100644
--- a/third_party/WebKit/Source/core/layout/LayoutBlockFlow.cpp
+++ b/third_party/WebKit/Source/core/layout/LayoutBlockFlow.cpp
@@ -4149,21 +4149,23 @@ void LayoutBlockFlow::UpdateAncestorShouldPaintFloatingObject(
       break;
 
     FloatingObject& floating_object = **it;
-    if (!float_box_is_self_painting_layer) {
-      // This repeats the logic in addOverhangingFloats() about shouldPaint
-      // flag:
-      // - The nearest enclosing block in which the float doesn't overhang
-      //   paints the float;
-      // - Or even if the float overhangs, if the ancestor block has
-      //   self-painting layer, it paints the float.
-      if (ancestor_block->HasSelfPaintingLayer() ||
-          !ancestor_block->IsOverhangingFloat(floating_object)) {
-        floating_object.SetShouldPaint(true);
-        return;
-      }
-    } else {
-      floating_object.SetShouldPaint(false);
-    }
+    // This repeats the logic in addOverhangingFloats() about shouldPaint
+    // flag:
+    // - The nearest enclosing block in which the float doesn't overhang
+    //   paints the float;
+    // - Or even if the float overhangs, if the ancestor block has
+    //   self-painting layer, it paints the float.
+    LayoutBlockFlow* parent_block =
+        ToLayoutBlockFlow(floating_object.GetLayoutObject()->Parent());
+    bool is_overhanging_float =
+        parent_block && parent_block->IsOverhangingFloat(floating_object);
+    bool should_paint =
+        !float_box_is_self_painting_layer &&
+        (ancestor_block->HasSelfPaintingLayer() || !is_overhanging_float);
+    floating_object.SetShouldPaint(should_paint);
+
+    if (floating_object.ShouldPaint())
+      return;
   }
 }