[Android WebView] Treat zero values in viewport arguments specially

Source/core/dom/ViewportArguments.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2012-2013 Intel Corporation. All rights reserved.
  *
@@ skipping 148 matching lines @@
 
         PageScaleConstraints result;
         result.minimumScale = resultMinZoom;
         result.maximumScale = resultMaxZoom;
         result.initialScale = resultZoom;
         result.layoutSize.setWidth(resultWidth);
         result.layoutSize.setHeight(resultHeight);
         return result;
     }
 
+    if (type == ViewportArguments::ViewportMetaLayoutSizeAndZeroValuesQuirk) {
+        if (!static_cast<int>(resultWidth)) {
+            resultWidth = ViewportArguments::ValueDeviceWidth;
+            if (!static_cast<int>(resultZoom))
+                resultZoom = 1.0;
+        }
+        if (!static_cast<int>(resultHeight))
+            resultHeight = ViewportArguments::ValueDeviceHeight;
+        if (!static_cast<int>(resultMinZoom))
+            resultMinZoom = ViewportArguments::ValueAuto;
+        if (!static_cast<int>(resultMaxZoom))
+            resultMaxZoom = ViewportArguments::ValueAuto;
+    }
+
     switch (static_cast<int>(resultWidth)) {
     case ViewportArguments::ValueDeviceWidth:
         resultWidth = initialViewportSize.width();
         break;
     case ViewportArguments::ValueDeviceHeight:
         resultWidth = initialViewportSize.height();
         break;
     }
 
     switch (static_cast<int>(resultHeight)) {
@@ skipping 255 matching lines @@
     if (!replacement1.isNull())
         message.replace("%replacement1", replacement1);
     if (!replacement2.isNull())
         message.replace("%replacement2", replacement2);
 
     // FIXME: This message should be moved off the console once a solution to https://bugs.webkit.org/show_bug.cgi?id=103274 exists.
     document->addConsoleMessage(RenderingMessageSource, viewportErrorMessageLevel(errorCode), message);
 }
 
 } // namespace WebCore