Adds scroll position/scale emulation to DevTools.

third_party/WebKit/Source/web/WebViewImpl.h

Index: third_party/WebKit/Source/web/WebViewImpl.h
diff --git a/third_party/WebKit/Source/web/WebViewImpl.h b/third_party/WebKit/Source/web/WebViewImpl.h
index 2c3e9a0aae1cef9784986fde5cf36ff1727e135d..f315e695d59ac1c71aacca018f4a2fc48ee9e407 100644
--- a/third_party/WebKit/Source/web/WebViewImpl.h
+++ b/third_party/WebKit/Source/web/WebViewImpl.h
@@ -69,6 +69,7 @@
 
 namespace blink {
 
+class CompositorMutatorImpl;
 class DataObject;
 class DevToolsEmulator;
 class Frame;
@@ -78,6 +79,7 @@ class LinkHighlightImpl;
 class PageOverlay;
 class PageScaleConstraintsSet;
 class PaintLayerCompositor;
+class ScrollAndScaleEmulator;
 class TopControls;
 class UserGestureToken;
 class WebActiveGestureAnimation;
@@ -87,7 +89,6 @@ class WebLayerTreeView;
 class WebLocalFrame;
 class WebLocalFrameImpl;
 class WebImage;
-class CompositorMutatorImpl;
 class WebPagePopupImpl;
 class WebPlugin;
 class WebRemoteFrame;
@@ -530,6 +531,12 @@ private:
     void setPageScaleFactorAndLocation(float, const FloatPoint&);
     void propagateZoomFactorToLocalFrameRoots(Frame*, float);
 
+    // Override the page scale and scroll positions of main frame and visual viewport.
+    void setScrollAndScaleOverride(const WebDeviceEmulationParams&);
+
+    // Clear the page scale and scroll position overrides.
+    void clearScrollAndScaleOverride();
+
     void scrollAndRescaleViewports(float scaleFactor, const IntPoint& mainFrameOrigin, const FloatPoint& visualViewportOrigin);
 
     float maximumLegiblePageScale() const;
@@ -675,6 +682,8 @@ private:
     float m_fakePageScaleAnimationPageScaleFactor;
     bool m_fakePageScaleAnimationUseAnchor;
 
+    RefPtr<ScrollAndScaleEmulator> m_scrollAndScaleEmulator;

[bokan, 2016/07/04 22:44:09]

I think this should move to FrameHost (see reply to comment on earlier
patchset).

[Eric Seckler, 2016/07/05 16:46:51]

Done.

+
     bool m_doingDragAndDrop;
 
     bool m_ignoreInputEvents;