[compositor-worker] root scrolling layer is associated with document scrolling element

third_party/WebKit/Source/bindings/core/v8/serialization/V8ScriptValueDeserializer.cpp

Index: third_party/WebKit/Source/bindings/core/v8/serialization/V8ScriptValueDeserializer.cpp
diff --git a/third_party/WebKit/Source/bindings/core/v8/serialization/V8ScriptValueDeserializer.cpp b/third_party/WebKit/Source/bindings/core/v8/serialization/V8ScriptValueDeserializer.cpp
index 68a6afc8a19218f4806cea2fa23a8907a15da54b..07de0ac2654f8c23d193f0767794d482860cb493 100644
--- a/third_party/WebKit/Source/bindings/core/v8/serialization/V8ScriptValueDeserializer.cpp
+++ b/third_party/WebKit/Source/bindings/core/v8/serialization/V8ScriptValueDeserializer.cpp
@@ -135,15 +135,17 @@ ScriptWrappable* V8ScriptValueDeserializer::readDOMObject(
     }
     case CompositorProxyTag: {
       uint64_t element;
+      uint64_t scrollingElement;
       uint32_t properties;
       const uint32_t validPropertiesMask = static_cast<uint32_t>(
           (1u << CompositorMutableProperty::kNumProperties) - 1);
       if (!RuntimeEnabledFeatures::compositorWorkerEnabled() ||
-          !readUint64(&element) || !readUint32(&properties) || !properties ||
+          !readUint64(&element) || !readUint64(&scrollingElement) ||
+          !readUint32(&properties) || !properties ||
           (properties & ~validPropertiesMask))
         return nullptr;
       return CompositorProxy::create(m_scriptState->getExecutionContext(),
-                                     element, properties);
+                                     element, scrollingElement, properties);
     }
     case FileTag:
       return readFile();