[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 11 matching lines @@
  * along with this library; see the file COPYING.LIB.  If not, write to
  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  *
  */
 
 #include "config.h"
 #include "core/dom/ViewportArguments.h"
 
 #include "core/dom/Document.h"
+#include "core/page/Page.h"
+#include "core/page/Settings.h"
 #include "wtf/text/WTFString.h"
 
 using namespace std;
 
 namespace WebCore {
 
 static const float& compareIgnoringAuto(const float& value1, const float& value2, const float& (*compare) (const float&, const float&))
 {
     if (value1 == ViewportArguments::ValueAuto)
         return value2;
@@ skipping 248 matching lines @@
     if (equalIgnoringCase(valueString, "device-width"))
         return ViewportArguments::ValueDeviceWidth;
     if (equalIgnoringCase(valueString, "device-height"))
         return ViewportArguments::ValueDeviceHeight;
 
     float value = numericPrefix(keyString, valueString, document);
 
     if (value < 0)
         return ViewportArguments::ValueAuto;
 
+    if (!static_cast<int>(value) && document->page() && document->page()->settings().viewportMetaZeroValuesQuirk()) {
+        if (keyString == "width")
+            return ViewportArguments::ValueDeviceWidth;
+        if (keyString == "height")
+            return ViewportArguments::ValueDeviceHeight;
+    }
+
     return value;
 }
 
 static float findScaleValue(const String& keyString, const String& valueString, Document* document)
 {
     // 1) Non-negative number values are translated to <number> values.
     // 2) Negative number values are translated to auto.
     // 3) yes is translated to 1.0.
     // 4) device-width and device-height are translated to 10.0.
     // 5) no and unknown values are translated to 0.0
 
     if (equalIgnoringCase(valueString, "yes"))
         return 1;
     if (equalIgnoringCase(valueString, "no"))
         return 0;
     if (equalIgnoringCase(valueString, "device-width"))
         return 10;
     if (equalIgnoringCase(valueString, "device-height"))
         return 10;
 
     float value = numericPrefix(keyString, valueString, document);
 
     if (value < 0)
         return ViewportArguments::ValueAuto;
 
     if (value > 10.0)
         reportViewportWarning(document, MaximumScaleTooLargeError, String(), String());
 
+    if (!static_cast<int>(value) && document->page() && document->page()->settings().viewportMetaZeroValuesQuirk() && (keyString == "minimum-scale" || keyString == "maximum-scale"))
+        return ViewportArguments::ValueAuto;
+
     return value;
 }
 
 static float findUserScalableValue(const String& keyString, const String& valueString, Document* document)
 {
     // yes and no are used as keywords.
     // Numbers >= 1, numbers <= -1, device-width and device-height are mapped to yes.
     // Numbers in the range <-1, 1>, and unknown values, are mapped to no.
 
     if (equalIgnoringCase(valueString, "yes"))
@@ skipping 96 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