Carry out a resize even if no layout has been performed.

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 1588 matching lines @@
             m_verticalScrollbar->setElasticOverscroll(elasticOverscroll.height());
             scrollAnimator()->notifyContentAreaScrolled(FloatSize(0, delta));
             if (!m_scrollbarsSuppressed)
                 m_verticalScrollbar->invalidate();
         }
     }
 }
 
 IntSize FrameView::layoutSize(IncludeScrollbarsInRect scrollbarInclusion) const
 {
-    return scrollbarInclusion == ExcludeScrollbars ? excludeScrollbars(m_layoutSize) : m_layoutSize;
+    IntSize ret = scrollbarInclusion == ExcludeScrollbars ? excludeScrollbars(m_layoutSize) : m_layoutSize;
+    if (m_frame->settings()->forceZeroLayoutHeight())
+        ret.setHeight(0);
+    return ret;
 }
 
 void FrameView::setLayoutSize(const IntSize& size)
 {
     ASSERT(!layoutSizeFixedToFrameSize());
 
     setLayoutSizeInternal(size);
 }
 
 void FrameView::scrollPositionChanged()
@@ skipping 1439 matching lines @@
 
 void FrameView::setLayoutSizeInternal(const IntSize& size)
 {
     if (m_layoutSize == size)
         return;
 
     m_layoutSize = size;
     contentsResized();
 }
 
+void FrameView::didChangeForceLayoutHeightMode()
+{
+    contentsResized();
+}
+
 void FrameView::didAddScrollbar(Scrollbar* scrollbar, ScrollbarOrientation orientation)
 {
     ScrollableArea::didAddScrollbar(scrollbar, orientation);
     if (AXObjectCache* cache = axObjectCache())
         cache->handleScrollbarUpdate(this);
 }
 
 void FrameView::willRemoveScrollbar(Scrollbar* scrollbar, ScrollbarOrientation orientation)
 {
     ScrollableArea::willRemoveScrollbar(scrollbar, orientation);
@@ skipping 953 matching lines @@
 {
     Settings* settings = frame().settings();
     if (!settings || !settings->rootLayerScrolls())
         return this;
 
     RenderView* renderView = this->renderView();
     return renderView ? renderView->scrollableArea() : nullptr;
 }
 
 } // namespace blink