Correct data size argument type in resource loading path to unsigned

Source/core/fetch/Resource.cpp

 /*
     Copyright (C) 1998 Lars Knoll (knoll@mpi-hd.mpg.de)
     Copyright (C) 2001 Dirk Mueller (mueller@kde.org)
     Copyright (C) 2002 Waldo Bastian (bastian@kde.org)
     Copyright (C) 2006 Samuel Weinig (sam.weinig@gmail.com)
     Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 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
@@ skipping 195 matching lines @@
 void Resource::checkNotify()
 {
     if (isLoading())
         return;
 
     ResourceClientWalker<ResourceClient> w(m_clients);
     while (ResourceClient* c = w.next())
         c->notifyFinished(this);
 }
 
-void Resource::appendData(const char* data, int length)
+void Resource::appendData(const char* data, unsigned length)
 {
     TRACE_EVENT0("blink", "Resource::appendData");
     ASSERT(!m_resourceToRevalidate);
     ASSERT(!errorOccurred());
     if (m_options.dataBufferingPolicy == DoNotBufferData)
         return;
     if (m_data)
         m_data->append(data, length);
     else
         m_data = SharedBuffer::createPurgeable(data, length);
@@ skipping 790 matching lines @@
         return "ImportResource";
     case Resource::Media:
         return "Media";
     }
     ASSERT_NOT_REACHED();
     return "Unknown";
 }
 #endif // !LOG_DISABLED
 
 }