Adds scroll position/scale emulation to DevTools.

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

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
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  * modification, are permitted provided that the following conditions
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  *
  * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY
  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  * DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY
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 #include "core/page/scrolling/ScrollingCoordinator.h"
 
 #include "core/css/CSSStyleSheet.h"
 #include "core/css/StyleSheetList.h"
+#include "core/frame/FrameHost.h"
 #include "core/frame/FrameView.h"
+#include "core/frame/VisualViewport.h"
 #include "core/layout/LayoutPart.h"
 #include "core/layout/api/LayoutViewItem.h"
 #include "core/layout/compositing/CompositedLayerMapping.h"
 #include "core/layout/compositing/PaintLayerCompositor.h"
 #include "core/page/Page.h"
 #include "platform/graphics/GraphicsLayer.h"
 #include "platform/testing/URLTestHelpers.h"
 #include "public/platform/Platform.h"
 #include "public/platform/WebLayer.h"
 #include "public/platform/WebLayerPositionConstraint.h"
@@ skipping 85 matching lines @@
     Page* page = frame()->page();
     ASSERT_TRUE(page->scrollingCoordinator());
     ASSERT_TRUE(page->scrollingCoordinator()->coordinatesScrollingForFrameView(frameView));
 
     // Fast scrolling should be enabled by default.
     WebLayer* rootScrollLayer = getRootScrollLayer();
     ASSERT_TRUE(rootScrollLayer->scrollable());
     ASSERT_FALSE(rootScrollLayer->shouldScrollOnMainThread());
     ASSERT_EQ(WebEventListenerProperties::Nothing, webLayerTreeView()->eventListenerProperties(WebEventListenerClass::TouchStartOrMove));
     ASSERT_EQ(WebEventListenerProperties::Nothing, webLayerTreeView()->eventListenerProperties(WebEventListenerClass::MouseWheel));
+
+    WebLayer* innerViewportScrollLayer = page->frameHost().visualViewport().scrollLayer()->platformLayer();
+    ASSERT_TRUE(innerViewportScrollLayer->scrollable());
+    ASSERT_FALSE(innerViewportScrollLayer->shouldScrollOnMainThread());
 }
 
 TEST_F(ScrollingCoordinatorTest, fastScrollingCanBeDisabledWithSetting)
 {
     navigateTo("about:blank");
     webViewImpl()->settings()->setThreadedScrollingEnabled(false);
     forceFullCompositingUpdate();
 
     // Make sure the scrolling coordinator is active.
     FrameView* frameView = frame()->view();
     Page* page = frame()->page();
     ASSERT_TRUE(page->scrollingCoordinator());
     ASSERT_TRUE(page->scrollingCoordinator()->coordinatesScrollingForFrameView(frameView));
 
     // Main scrolling should be enabled with the setting override.
     WebLayer* rootScrollLayer = getRootScrollLayer();
     ASSERT_TRUE(rootScrollLayer->scrollable());
     ASSERT_TRUE(rootScrollLayer->shouldScrollOnMainThread());
+
+    // Main scrolling should also propagate to inner viewport layer.
+    WebLayer* innerViewportScrollLayer = page->frameHost().visualViewport().scrollLayer()->platformLayer();
+    ASSERT_TRUE(innerViewportScrollLayer->scrollable());
+    ASSERT_TRUE(innerViewportScrollLayer->shouldScrollOnMainThread());
 }
 
 
 TEST_F(ScrollingCoordinatorTest, fastFractionalScrollingDiv)
 {
     bool origFractionalOffsetsEnabled = RuntimeEnabledFeatures::fractionalScrollOffsetsEnabled();
     RuntimeEnabledFeatures::setFractionalScrollOffsetsEnabled(true);
 
     registerMockedHttpURLLoad("fractional-scroll-div.html");
     navigateTo(m_baseURL + "fractional-scroll-div.html");
@@ skipping 502 matching lines @@
     // remove custom scrollbar class, the scrollbar is expected to scroll on
     // impl thread as it is an overlay scrollbar.
     container->removeAttribute("class");
     forceFullCompositingUpdate();
     scrollbarGraphicsLayer = compositedLayerMapping->layerForVerticalScrollbar();
     ASSERT_FALSE(scrollbarGraphicsLayer->platformLayer()->shouldScrollOnMainThread());
     ASSERT_FALSE(scrollbarGraphicsLayer->platformLayer()->mainThreadScrollingReasons() & MainThreadScrollingReason::kCustomScrollbarScrolling);
 }
 
 } // namespace blink