Fix double-offset issue of RenderObject::positionFromPaintInvalidationContainer()

Source/core/rendering/RenderObject.cpp

Index: Source/core/rendering/RenderObject.cpp
diff --git a/Source/core/rendering/RenderObject.cpp b/Source/core/rendering/RenderObject.cpp
index 9e72e470370fa9960797db03a40b95aec44e7459..43d6bd391a1776d363540b3529ca2df553255b20 100644
--- a/Source/core/rendering/RenderObject.cpp
+++ b/Source/core/rendering/RenderObject.cpp
@@ -1324,11 +1324,10 @@ LayoutPoint RenderObject::positionFromPaintInvalidationContainer(const RenderLay
     // FIXME: This assert should be re-enabled when we move paint invalidation to after compositing update. crbug.com/360286
     // ASSERT(containerForPaintInvalidation() == paintInvalidationContainer);
 
-    LayoutPoint offset = isBox() ? toRenderBox(this)->location() : LayoutPoint();
     if (paintInvalidationContainer == this)
-        return offset;
+        return LayoutPoint();
 
-    return roundedIntPoint(localToContainerPoint(offset, paintInvalidationContainer, 0, 0, paintInvalidationState));
+    return LayoutPoint(localToContainerPoint(LayoutPoint(), paintInvalidationContainer, 0, 0, paintInvalidationState));
 }
 
 IntRect RenderObject::absoluteBoundingBoxRect() const