ViewPainter should skip background in print economy mode

Source/core/paint/BoxPainter.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "core/paint/BoxPainter.h"
 
 #include "core/HTMLNames.h"
 #include "core/frame/Settings.h"
 #include "core/html/HTMLFrameOwnerElement.h"
@@ skipping 294 matching lines @@
     bool includeRightEdge = box ? box->includeLogicalRightEdge() : true;
 
     bool hasRoundedBorder = obj.style()->hasBorderRadius() && (includeLeftEdge || includeRightEdge);
     bool clippedWithLocalScrolling = obj.hasOverflowClip() && bgLayer.attachment() == LocalBackgroundAttachment;
     bool isBorderFill = bgLayer.clip() == BorderFillBox;
     bool isBottomLayer = !bgLayer.next();
 
     Color bgColor = color;
     StyleImage* bgImage = bgLayer.image();
 
-    bool forceBackgroundToWhite = false;
-    if (obj.document().printing()) {
-        if (obj.style()->printColorAdjust() == PrintColorAdjustEconomy)
-            forceBackgroundToWhite = true;
-        if (obj.document().settings() && obj.document().settings()->shouldPrintBackgrounds())
-            forceBackgroundToWhite = false;
-    }
+    bool forceBackgroundToWhite = shouldForceWhiteBackgroundForPrintEconomy(obj.styleRef(), obj.document());
 
     // When printing backgrounds is disabled or using economy mode,
     // change existing background colors and images to a solid white background.
     // If there's no bg color or image, leave it untouched to avoid affecting transparency.
     // We don't try to avoid loading the background images, because this style flag is only set
     // when printing, and at that point we've already loaded the background images anyway. (To avoid
     // loading the background images we'd have to do this check when applying styles rather than
     // while layout.)
     if (forceBackgroundToWhite) {
         // Note that we can't reuse this variable below because the bgColor might be changed
@@ skipping 716 matching lines @@
                     clippedEdges |= GraphicsContext::RightEdge;
                 else
                     clippedEdges |= GraphicsContext::BottomEdge;
             }
             // TODO: support non-integer shadows - crbug.com/334828
             context->drawInnerShadow(border, shadowColor, flooredIntSize(shadowOffset), shadowBlur, shadowSpread, clippedEdges);
         }
     }
 }
 
+bool BoxPainter::shouldForceWhiteBackgroundForPrintEconomy(const ComputedStyle& style, const Document& document)
+{
+    return document.printing() && style.printColorAdjust() == PrintColorAdjustEconomy
+        && (!document.settings() || !document.settings()->shouldPrintBackgrounds());
+}
+
 } // namespace blink