Initial containing block for print not affected by page zoom.

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 1387 matching lines @@
     if (parentRect.isEmpty())
       return IntRect();
 
     us.intersect(parentRect);
   }
 
   return us;
 }
 
 FloatSize FrameView::viewportSizeForViewportUnits() const {
-  float zoom = frame().pageZoomFactor();
+  float zoom = 1;
+  if (!m_frame->document() || !m_frame->document()->printing())
+    zoom = frame().pageZoomFactor();

[rune, 2017/03/09 22:04:55]

I have kept this change since this is what fixes issue 699910.

[bokan, 2017/03/09 22:58:06]

Acknowledged.

 
   LayoutViewItem layoutViewItem = this->layoutViewItem();
   if (layoutViewItem.isNull())
     return FloatSize();
 
   FloatSize layoutSize;
   layoutSize.setWidth(layoutViewItem.viewWidth(IncludeScrollbars) / zoom);
   layoutSize.setHeight(layoutViewItem.viewHeight(IncludeScrollbars) / zoom);
 
   BrowserControls& browserControls = m_frame->page()->browserControls();
   if (RuntimeEnabledFeatures::inertTopControlsEnabled() &&
       browserControls.permittedState() != WebBrowserControlsHidden) {
     // We use the layoutSize rather than frameRect to calculate viewport units
     // so that we get correct results on mobile where the page is laid out into
     // a rect that may be larger than the viewport (e.g. the 980px fallback
     // width for desktop pages). Since the layout height is statically set to
     // be the viewport with browser controls showing, we add the browser
     // controls height, compensating for page scale as well, since we want to
     // use the viewport with browser controls hidden for vh (to match Safari).
     int viewportWidth = m_frame->host()->visualViewport().size().width();
     if (m_frame->isMainFrame() && layoutSize.width() && viewportWidth) {
       float pageScaleAtLayoutWidth = viewportWidth / layoutSize.width();
       layoutSize.expand(0, browserControls.height() / pageScaleAtLayoutWidth);
     }
   }
 
   return layoutSize;
 }
 
+FloatSize FrameView::viewportSizeForMediaQueries() const {
+  FloatSize viewportSize(layoutSize());
+  if (!m_frame->document() || !m_frame->document()->printing())
+    viewportSize.scale(1 / frame().pageZoomFactor());
+  return viewportSize;
+}
+
 DocumentLifecycle& FrameView::lifecycle() const {
   DCHECK(m_frame);
   DCHECK(m_frame->document());
   return m_frame->document()->lifecycle();
 }
 
 LayoutReplaced* FrameView::embeddedReplacedContent() const {
   LayoutViewItem layoutViewItem = this->layoutViewItem();
   if (layoutViewItem.isNull())
     return nullptr;
@@ skipping 3805 matching lines @@
 void FrameView::setAnimationHost(
     std::unique_ptr<CompositorAnimationHost> host) {
   m_animationHost = std::move(host);
 }
 
 LayoutUnit FrameView::caretWidth() const {
   return LayoutUnit(getHostWindow()->windowToViewportScalar(1));
 }
 
 }  // namespace blink