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

Source/core/frame/FrameView.cpp

Index: Source/core/frame/FrameView.cpp
diff --git a/Source/core/frame/FrameView.cpp b/Source/core/frame/FrameView.cpp
index 27f746bed86e6caa4dd6ac1c737daa4c888f456a..488cf66d086e3567d278832b94fa6a55d1903c52 100644
--- a/Source/core/frame/FrameView.cpp
+++ b/Source/core/frame/FrameView.cpp
@@ -1606,7 +1606,10 @@ void FrameView::setElasticOverscroll(const FloatSize& elasticOverscroll)
 
 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)
@@ -3066,6 +3069,11 @@ void FrameView::setLayoutSizeInternal(const IntSize& size)
     contentsResized();
 }
 
+void FrameView::didChangeForceLayoutHeightMode()
+{
+    contentsResized();
+}
+
 void FrameView::didAddScrollbar(Scrollbar* scrollbar, ScrollbarOrientation orientation)
 {
     ScrollableArea::didAddScrollbar(scrollbar, orientation);