Mark only self for invalidation if inside pre-paint.

Marking the entire ancestry for invalidation while inside pre-paint
probably isn't too healthy anyway, and when the pre paint machinery is
updated to walk the NG physical fragment tree rather than the layout
object tree, we're potentially going to visit the same layout object
more than once, and not always in exact tree order.

Bug: 1043787
Change-Id: Id99f46f4704cc279323a94a80762c4e0d2cd166b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2089832Reviewed-by: Xianzhu Wang <wangxianzhu@chromium.org>
Reviewed-by: Philip Rogers <pdr@chromium.org>
Commit-Queue: Morten Stenshorne <mstensho@chromium.org>
Cr-Commit-Position: refs/heads/master@{#747470}

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

@@ -2279,7 +2279,13 @@ class CORE_EXPORT LayoutObject : public ImageResourceObserver,
       }
     }
     void SetShouldCheckForPaintInvalidation() {
-      layout_object_.SetShouldCheckForPaintInvalidation();
+      // This method is only intended to be called when visiting this object
+      // during pre-paint, and as such it should only mark itself, and not the
+      // entire containing block chain.
+      DCHECK_EQ(layout_object_.GetDocument().Lifecycle().GetState(),
+                DocumentLifecycle::kInPrePaint);
+      layout_object_.bitfields_.SetNeedsPaintOffsetAndVisualRectUpdate(true);
+      layout_object_.bitfields_.SetShouldCheckForPaintInvalidation(true);
     }
     void SetShouldDoFullPaintInvalidation(PaintInvalidationReason reason) {
       layout_object_.SetShouldDoFullPaintInvalidation(reason);