scroll: Tell the platform layer whether it can be scrolled by the user.

Source/web/tests/ScrollingCoordinatorChromiumTest.cpp

 /*
  * Copyright (C) 2012 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:
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
  *     notice, this list of conditions and the following disclaimer in the
@@ skipping 285 matching lines @@
 
     CompositedLayerMapping* compositedLayerMapping = layer->compositedLayerMapping();
     ASSERT_TRUE(compositedLayerMapping->hasScrollingLayer());
     ASSERT(compositedLayerMapping->scrollingContentsLayer());
 
     GraphicsLayer* graphicsLayer = compositedLayerMapping->scrollingContentsLayer();
     ASSERT_EQ(layer->scrollableArea(), graphicsLayer->scrollableArea());
 
     WebLayer* webScrollLayer = compositedLayerMapping->scrollingContentsLayer()->platformLayer();
     ASSERT_TRUE(webScrollLayer->scrollable());
+    ASSERT_TRUE(webScrollLayer->userScrollableHorizontal());
+    ASSERT_TRUE(webScrollLayer->userScrollableVertical());
 
 #if OS(ANDROID)
     // Now verify we've attached impl-side scrollbars onto the scrollbar layers
     ASSERT_TRUE(compositedLayerMapping->layerForHorizontalScrollbar());
     ASSERT_TRUE(compositedLayerMapping->layerForHorizontalScrollbar()->hasContentsLayer());
     ASSERT_TRUE(compositedLayerMapping->layerForVerticalScrollbar());
     ASSERT_TRUE(compositedLayerMapping->layerForVerticalScrollbar()->hasContentsLayer());
 #endif
 }
 
+TEST_F(ScrollingCoordinatorChromiumTest, overflowHidden)
+{
+    registerMockedHttpURLLoad("overflow-hidden.html");
+    navigateTo(m_baseURL + "overflow-hidden.html");
+
+    // Verify the properties of the accelerated scrolling element starting from the RenderObject
+    // all the way to the WebLayer.
+    Element* overflowElement = m_webViewImpl->mainFrameImpl()->frame()->document()->getElementById("unscrollable-y");
+    ASSERT(overflowElement);
+
+    RenderObject* renderer = overflowElement->renderer();
+    ASSERT_TRUE(renderer->isBoxModelObject());
+    ASSERT_TRUE(renderer->hasLayer());
+
+    RenderLayer* layer = toRenderBoxModelObject(renderer)->layer();
+    ASSERT_TRUE(layer->usesCompositedScrolling());
+    ASSERT_EQ(PaintsIntoOwnBacking, layer->compositingState());
+
+    CompositedLayerMapping* compositedLayerMapping = layer->compositedLayerMapping();
+    ASSERT_TRUE(compositedLayerMapping->hasScrollingLayer());
+    ASSERT(compositedLayerMapping->scrollingContentsLayer());
+
+    GraphicsLayer* graphicsLayer = compositedLayerMapping->scrollingContentsLayer();
+    ASSERT_EQ(layer->scrollableArea(), graphicsLayer->scrollableArea());
+
+    WebLayer* webScrollLayer = compositedLayerMapping->scrollingContentsLayer()->platformLayer();
+    ASSERT_TRUE(webScrollLayer->scrollable());
+    ASSERT_TRUE(webScrollLayer->userScrollableHorizontal());
+    ASSERT_FALSE(webScrollLayer->userScrollableVertical());
+
+    overflowElement = m_webViewImpl->mainFrameImpl()->frame()->document()->getElementById("unscrollable-x");
+    ASSERT(overflowElement);
+
+    renderer = overflowElement->renderer();
+    ASSERT_TRUE(renderer->isBoxModelObject());
+    ASSERT_TRUE(renderer->hasLayer());
+
+    layer = toRenderBoxModelObject(renderer)->layer();
+    ASSERT_TRUE(layer->usesCompositedScrolling());
+    ASSERT_EQ(PaintsIntoOwnBacking, layer->compositingState());
+
+    compositedLayerMapping = layer->compositedLayerMapping();
+    ASSERT_TRUE(compositedLayerMapping->hasScrollingLayer());
+    ASSERT(compositedLayerMapping->scrollingContentsLayer());
+
+    graphicsLayer = compositedLayerMapping->scrollingContentsLayer();
+    ASSERT_EQ(layer->scrollableArea(), graphicsLayer->scrollableArea());
+
+    webScrollLayer = compositedLayerMapping->scrollingContentsLayer()->platformLayer();
+    ASSERT_TRUE(webScrollLayer->scrollable());
+    ASSERT_FALSE(webScrollLayer->userScrollableHorizontal());
+    ASSERT_TRUE(webScrollLayer->userScrollableVertical());
+}
+
 TEST_F(ScrollingCoordinatorChromiumTest, iframeScrolling)
 {
     registerMockedHttpURLLoad("iframe-scrolling.html");
     registerMockedHttpURLLoad("iframe-scrolling-inner.html");
     navigateTo(m_baseURL + "iframe-scrolling.html");
 
     // Verify the properties of the accelerated scrolling element starting from the RenderObject
     // all the way to the WebLayer.
     Element* scrollableFrame = m_webViewImpl->mainFrameImpl()->frame()->document()->getElementById("scrollable");
     ASSERT_TRUE(scrollableFrame);
@@ skipping 71 matching lines @@
 
 TEST_F(ScrollingCoordinatorChromiumTest, setupScrollbarLayerShouldNotCrash)
 {
     registerMockedHttpURLLoad("setup_scrollbar_layer_crash.html");
     navigateTo(m_baseURL + "setup_scrollbar_layer_crash.html");
     // This test document setup an iframe with scrollbars, then switch to
     // an empty document by javascript.
 }
 
 } // namespace