Adds DevTools commands for forced viewport override.

third_party/WebKit/Source/core/frame/FrameView.cpp

 /*
  * Copyright (C) 1998, 1999 Torben Weis <weis@kde.org>
  *                     1999 Lars Knoll <knoll@kde.org>
  *                     1999 Antti Koivisto <koivisto@kde.org>
  *                     2000 Dirk Mueller <mueller@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
  *           (C) 2006 Graham Dennis (graham.dennis@gmail.com)
  *           (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
@@ skipping 140 matching lines @@
     , m_needsUpdateWidgetGeometries(false)
     , m_needsUpdateViewportIntersection(true)
     , m_needsUpdateViewportIntersectionInSubtree(true)
 #if ENABLE(ASSERT)
     , m_hasBeenDisposed(false)
 #endif
     , m_horizontalScrollbarMode(ScrollbarAuto)
     , m_verticalScrollbarMode(ScrollbarAuto)
     , m_horizontalScrollbarLock(false)
     , m_verticalScrollbarLock(false)
+    , m_visibleContentRectForRecording(nullptr)
     , m_scrollbarsAvoidingResizer(0)
     , m_scrollbarsSuppressed(false)
     , m_inUpdateScrollbars(false)
     , m_frameTimingRequestsDirty(true)
     , m_viewportIntersectionValid(false)
     , m_hiddenForThrottling(false)
     , m_crossOriginForThrottling(false)
     , m_subtreeThrottled(false)
     , m_currentUpdateLifecyclePhasesTargetState(DocumentLifecycle::Uninitialized)
     , m_suppressAdjustViewSize(false)
@@ skipping 3131 matching lines @@
 IntRect FrameView::visibleContentRect(IncludeScrollbarsInRect scrollbarInclusion) const
 {
     return IntRect(flooredIntPoint(m_scrollPosition), visibleContentSize(scrollbarInclusion));
 }
 
 IntSize FrameView::contentsSize() const
 {
     return m_contentsSize;
 }
 
+IntSize FrameView::visibleContentSizeForRecording() const
+{
+    return visibleContentRectForRecording().size();
+}
+
+IntRect FrameView::visibleContentRectForRecording() const
+{
+    if (m_visibleContentRectForRecording)
+        return *m_visibleContentRectForRecording;
+    return visibleContentRect();
+}
+
+void FrameView::setVisibleContentRectForRecording(const IntRect& rect)
+{
+    m_visibleContentRectForRecording.reset(new IntRect(rect));
+}
+
+void FrameView::resetVisibleContentRectForRecording()
+{
+    m_visibleContentRectForRecording.reset();
+}
+
 IntPoint FrameView::minimumScrollPosition() const
 {
     return IntPoint(-scrollOrigin().x(), -scrollOrigin().y());
 }
 
 void FrameView::adjustScrollbarOpacity()
 {
     if (m_horizontalScrollbar && layerForHorizontalScrollbar()) {
         bool isOpaqueScrollbar = !m_horizontalScrollbar->isOverlayScrollbar();
         layerForHorizontalScrollbar()->setContentsOpaque(isOpaqueScrollbar);
@@ skipping 57 matching lines @@
         layoutViewItem.clearHitTestCache();
     }
 
     if (m_didScrollTimer.isActive())
         m_didScrollTimer.stop();
     m_didScrollTimer.startOneShot(resourcePriorityUpdateDelayAfterScroll, BLINK_FROM_HERE);
 
     if (AXObjectCache* cache = m_frame->document()->existingAXObjectCache())
         cache->handleScrollPositionChanged(this);
 
+    frame().host()->chromeClient().mainFrameScrollOffsetChanged();

[Sami, 2016/08/11 10:09:07]

May need to guard this with m_frame->isMainFrame(). (I also wonder if we could
reuse the didChangeScrollOffset callback below?)

[Eric Seckler, 2016/08/11 11:34:45]

You're right, guarding it now. I looked into the didChangeScrollOffset callback,
but that seems to be used to notify the embedder. I'm using the ChromeClient
path, because that's already used for similar things, e.g.
pageScaleFactorChanged() and layoutChanged().

     frame().loader().saveScrollState();
     frame().loader().client()->didChangeScrollOffset();
 
     if (scrollType == CompositorScroll && m_frame->isMainFrame()) {
         if (DocumentLoader* documentLoader = m_frame->loader().documentLoader())
             documentLoader->initialScrollState().wasScrolledByUser = true;
     }
 
     if (scrollType != AnchoringScroll)
         clearScrollAnchor();
@@ skipping 848 matching lines @@
 }
 
 bool FrameView::canThrottleRendering() const
 {
     if (!RuntimeEnabledFeatures::renderingPipelineThrottlingEnabled())
         return false;
     return m_subtreeThrottled || (m_hiddenForThrottling && m_crossOriginForThrottling);
 }
 
 } // namespace blink