Deprecate fetching stylesheets with unsupported type

third_party/WebKit/Source/core/html/HTMLLinkElement.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, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2009 Rob Buis (rwlbuis@gmail.com)
  * Copyright (C) 2011 Google 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
@@ skipping 33 matching lines @@
 #include "core/frame/UseCounter.h"
 #include "core/frame/csp/ContentSecurityPolicy.h"
 #include "core/html/CrossOriginAttribute.h"
 #include "core/html/LinkManifest.h"
 #include "core/html/imports/LinkImport.h"
 #include "core/inspector/ConsoleMessage.h"
 #include "core/loader/FrameLoader.h"
 #include "core/loader/FrameLoaderClient.h"
 #include "core/loader/NetworkHintsInterface.h"
 #include "core/style/StyleInheritedData.h"
+#include "platform/ContentType.h"
+#include "platform/MIMETypeRegistry.h"
 #include "platform/RuntimeEnabledFeatures.h"
 #include "public/platform/Platform.h"
 #include "wtf/StdLibExtras.h"
 
 namespace blink {
 
 using namespace HTMLNames;
 
 template <typename CharacterType>
 static void parseSizes(const CharacterType* value, unsigned length, Vector<IntSize>& iconSizes)
@@ skipping 55 matching lines @@
         iconSizes.append(IntSize(width, height));
     }
 }
 
 static LinkEventSender& linkLoadEventSender()
 {
     DEFINE_STATIC_LOCAL(OwnPtrWillBePersistent<LinkEventSender>, sharedLoadEventSender, (LinkEventSender::create(EventTypeNames::load)));
     return *sharedLoadEventSender;
 }
 
+static bool styleSheetTypeIsSupported(const String& type)
+{
+    String trimmedType = ContentType(type).type();
+    return trimmedType.isEmpty() || MIMETypeRegistry::isSupportedStyleSheetMIMEType(trimmedType);
+}
+
 void HTMLLinkElement::parseSizesAttribute(const AtomicString& value, Vector<IntSize>& iconSizes)
 {
     ASSERT(iconSizes.isEmpty());
     if (value.isEmpty())
         return;
     if (value.is8Bit())
         parseSizes(value.characters8(), value.length(), iconSizes);
     else
         parseSizes(value.characters16(), value.length(), iconSizes);
 }
@@ skipping 567 matching lines @@
         if (!document().contentSecurityPolicy()->allowImageFromSource(builder.url()))
             return;
         if (document().frame() && document().frame()->loader().client())
             document().frame()->loader().client()->dispatchDidChangeIcons(m_owner->relAttribute().iconType());
     }
 
     if (!m_owner->loadLink(type, as, builder.url()))
         return;
 
     if (m_disabledState != Disabled && m_owner->relAttribute().isStyleSheet() && shouldLoadResource() && builder.url().isValid()) {
+        if (!styleSheetTypeIsSupported(type))
+            UseCounter::countDeprecation(document(), UseCounter::NonCSSStyleSheetType);
 
         if (resource()) {
             removePendingSheet();
             clearResource();
             clearFetchFollowingCORS();
         }
 
         if (!m_owner->shouldLoadLink())
             return;
 
@@ skipping 52 matching lines @@
 }
 
 DEFINE_TRACE(LinkStyle)
 {
     visitor->trace(m_sheet);
     LinkResource::trace(visitor);
     ResourceOwner<StyleSheetResource>::trace(visitor);
 }
 
 } // namespace blink