Remove paintOffsetTranslation for fixed-position elements.

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

Index: third_party/WebKit/Source/core/layout/LayoutBoxModelObject.cpp
diff --git a/third_party/WebKit/Source/core/layout/LayoutBoxModelObject.cpp b/third_party/WebKit/Source/core/layout/LayoutBoxModelObject.cpp
index 3271981ad0d0d28a9d695e1f70b0a6fd5115d775..fa54b5df1930a60176acf6a982bfa5a36b44867e 100644
--- a/third_party/WebKit/Source/core/layout/LayoutBoxModelObject.cpp
+++ b/third_party/WebKit/Source/core/layout/LayoutBoxModelObject.cpp
@@ -302,13 +302,6 @@ void LayoutBoxModelObject::styleDidChange(StyleDifference diff,
     // hasLayer status will affect whether to create localBorderBoxProperties.
     if (hadLayer != hasLayer()) {

[Xianzhu, 2016/12/15 22:37:11]

Nit:
if (RuntimeEnabledFeatures::slimmingPaintInvalidationEnabled() &&
    hadLayer != hasLayer()) {
 // hasLayer status will affect whether to create localBorderBoxProperties.
 setNeedsPaintPropertyUpdate();
}

       setNeedsPaintPropertyUpdate();
-    } else if (oldStyle && oldStyle->position() != styleRef().position() &&
-               (oldStyle->position() == FixedPosition ||
-                styleRef().position() == FixedPosition)) {
-      // Fixed-position status affects whether to create paintOffsetTranslation.
-      // TODO(chrishtr): Update the condition here when changing the condition
-      // in PaintPropertyTreeBuilder::updatePaintOffsetTranslation().
-      setNeedsPaintPropertyUpdate();
     }
   }