Viewport apply scroll should be on the document element not scrollingElement.

third_party/WebKit/Source/web/tests/WebFrameTest.cpp

 /*
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 8118 matching lines @@
 
     void ScrollByWheel(FrameTestHelpers::WebViewHelper* webViewHelper, int windowX, int windowY, float deltaX, float deltaY)
     {
         WebMouseWheelEvent event;
         event.type = WebInputEvent::MouseWheel;
         event.deltaX = deltaX;
         event.deltaY = deltaY;
         event.windowX = windowX;
         event.windowY = windowY;
         event.canScroll = true;
+        event.hasPreciseScrollingDeltas = true;
         webViewHelper->webViewImpl()->handleInputEvent(event);
     }
 
     void ScrollBegin(FrameTestHelpers::WebViewHelper* webViewHelper)
     {
         webViewHelper->webViewImpl()->handleInputEvent(generateEvent(WebInputEvent::GestureScrollBegin));
     }
 
     void ScrollUpdate(FrameTestHelpers::WebViewHelper* webViewHelper, float deltaX, float deltaY)
     {
@@ skipping 243 matching lines @@
     registerMockedHttpURLLoad("overscroll/overscroll.html");
     FrameTestHelpers::WebViewHelper webViewHelper;
     webViewHelper.initializeAndLoad(m_baseURL + "overscroll/overscroll.html", true, 0, &client, configureAndroid);
     webViewHelper.resize(WebSize(200, 200));
 
     EXPECT_CALL(client, didOverscroll(WebFloatSize(-1000, -1000), WebFloatSize(-1000, -1000), WebFloatPoint(), WebFloatSize()));
     ScrollByWheel(&webViewHelper, 10, 10, 1000, 1000);
     Mock::VerifyAndClearExpectations(&client);
 }
 
+TEST_P(WebFrameOverscrollTest, ScrollPageWithBodyExplicitlyOverflowing)
+{
+    RuntimeEnabledFeatures::setScrollTopLeftInteropEnabled(false);
+
+    OverscrollWebViewClient client;
+    registerMockedHttpURLLoad("mouse-wheel-overflow-body.html");
+    FrameTestHelpers::WebViewHelper webViewHelper;
+    webViewHelper.initializeAndLoad(m_baseURL + "mouse-wheel-overflow-body.html", true, 0, &client, configureAndroid);
+    webViewHelper.resize(WebSize(800, 600));
+
+    FrameView* view = webViewHelper.webViewImpl()->mainFrameImpl()->frameView();
+    Document* document = toWebLocalFrameImpl(webViewHelper.webViewImpl()->mainFrame())->frame()->document();
+
+    {
+        EXPECT_CALL(client, didOverscroll(_, _, _, _)).Times(0);
+        ScrollByWheel(&webViewHelper, 100, 100, 0, -450);
+
+        LayoutBox* layoutBody = toLayoutBox(document->body()->layoutObject());
+        ASSERT_EQ(400, layoutBody->getScrollableArea()->scrollPosition().y());
+        ASSERT_EQ(400, layoutBody->getScrollableArea()->maximumScrollPosition().y());
+
+        Mock::VerifyAndClearExpectations(&client);
+    }
+
+    view->setScrollPosition(DoublePoint(0, 0), ProgrammaticScroll);
+
+    {
+        EXPECT_CALL(client, didOverscroll(WebFloatSize(0, 200), WebFloatSize(0, 200), WebFloatPoint(), WebFloatSize()));
+        ScrollByWheel(&webViewHelper, 100, 100, 0, -300);
+
+        ASSERT_EQ(100, view->getScrollableArea()->scrollPosition().y());
+        ASSERT_EQ(100, view->getScrollableArea()->maximumScrollPosition().y());
+
+        Mock::VerifyAndClearExpectations(&client);
+    }
+}
+
 TEST_F(WebFrameTest, OrientationFrameDetach)
 {
     RuntimeEnabledFeatures::setOrientationEventEnabled(true);
     registerMockedHttpURLLoad("orientation-frame-detach.html");
     FrameTestHelpers::WebViewHelper webViewHelper;
     WebViewImpl* webViewImpl = webViewHelper.initializeAndLoad(m_baseURL + "orientation-frame-detach.html", true);
     webViewImpl->mainFrameImpl()->sendOrientationChangeEvent();
 }
 
 TEST_F(WebFrameTest, MaxFramesDetach)
@@ skipping 204 matching lines @@
     WebLocalFrame* mainFrame = helper.webView()->mainFrame()->toWebLocalFrame();
     v8::HandleScope scope(v8::Isolate::GetCurrent());
     mainFrame->executeScript(WebScriptSource("hello = 'world';"));
     FrameTestHelpers::loadFrame(mainFrame, "data:text/html,new page");
     v8::Local<v8::Value> result = mainFrame->executeScriptAndReturnValue(WebScriptSource("hello"));
     ASSERT_TRUE(result->IsString());
     EXPECT_EQ("world", toCoreString(result->ToString(mainFrame->mainWorldScriptContext()).ToLocalChecked()));
 }
 
 } // namespace blink