Need to clear viewport dependent units switching print mode.

third_party/WebKit/Source/core/css/resolver/StyleResolver.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 2004-2005 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2006, 2007 Nicholas Shanks (webkit@nickshanks.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 Apple Inc.
  * All rights reserved.
  * Copyright (C) 2007 Alexey Proskuryakov <ap@webkit.org>
  * Copyright (C) 2007, 2008 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved.
  * (http://www.torchmobile.com/)
@@ skipping 1899 matching lines @@
   for (CSSPropertyID property : properties) {
     if (property == CSSPropertyLineHeight)
       updateFont(state);
     StyleBuilder::applyProperty(property, state,
                                 *propertySet.getPropertyCSSValue(property));
   }
 }
 
 void StyleResolver::updateMediaType() {
   if (FrameView* view = document().view()) {
+    bool wasPrint = m_printMediaType;
     m_printMediaType =
         equalIgnoringCase(view->mediaType(), MediaTypeNames::print);
+    if (wasPrint != m_printMediaType)
+      m_matchedPropertiesCache.clearViewportDependent();
   }
 }
 
 DEFINE_TRACE(StyleResolver) {
   visitor->trace(m_matchedPropertiesCache);
   visitor->trace(m_selectorFilter);
   visitor->trace(m_styleSharingLists);
   visitor->trace(m_document);
   visitor->trace(m_tracker);
 }
 
 }  // namespace blink