Reduce viewport arguments parsing noise in the DevTools console

Source/core/html/HTMLMetaElement-in.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2003, 2010 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 315 matching lines @@
         }
         CASE("user-scalable") {
             description->userZoom = parseViewportValueAsUserZoom(keyString, valueString);
             return;
         }
         CASE("target-densitydpi") {
             description->deprecatedTargetDensityDPI = parseViewportValueAsDPI(keyString, valueString);
             reportViewportWarning(TargetDensityDpiUnsupported, String(), String());
             return;
         }
+        CASE("minimal-ui") {
+            // Ignore vendor-specific argument.
+            return;
+        }
     }
     reportViewportWarning(UnrecognizedViewportArgumentKeyError, keyString, String());
 }
 
 static const char* viewportErrorMessageTemplate(ViewportErrorCode errorCode)
 {
     static const char* const errors[] = {
         "The key \"%replacement1\" is not recognized and ignored.",
         "The value \"%replacement1\" for key \"%replacement2\" is invalid, and has been ignored.",
         "The value \"%replacement1\" for key \"%replacement2\" was truncated to its numeric prefix.",
         "The value for key \"maximum-scale\" is out of bounds and the value has been clamped.",
         "The key \"target-densitydpi\" is not supported.",
     };
 
     return errors[errorCode];
 }
 
 static MessageLevel viewportErrorMessageLevel(ViewportErrorCode errorCode)
 {
     switch (errorCode) {
     case TruncatedViewportArgumentValueError:
     case TargetDensityDpiUnsupported:
-        return WarningMessageLevel;
     case UnrecognizedViewportArgumentKeyError:
     case UnrecognizedViewportArgumentValueError:
     case MaximumScaleTooLargeError:
-        return ErrorMessageLevel;
+        return WarningMessageLevel;
     }
 
     ASSERT_NOT_REACHED();
     return ErrorMessageLevel;
 }
 
 void HTMLMetaElement::reportViewportWarning(ViewportErrorCode errorCode, const String& replacement1, const String& replacement2)
 {
     if (!document().frame())
         return;
@@ skipping 106 matching lines @@
 {
     return getAttribute(http_equivAttr);
 }
 
 const AtomicString& HTMLMetaElement::name() const
 {
     return getNameAttribute();
 }
 
 }