Fix sky include guards to match Chromium style

sky/engine/core/dom/AttributeCollection.h

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  * Copyright (C) 2014 Apple Inc. All rights reserved.
  * Copyright (C) 2014 Samsung Electronics. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
@@ skipping 12 matching lines @@
  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-#ifndef AttributeCollection_h
-#define AttributeCollection_h
+#ifndef SKY_ENGINE_CORE_DOM_ATTRIBUTECOLLECTION_H_
+#define SKY_ENGINE_CORE_DOM_ATTRIBUTECOLLECTION_H_
 
 #include "sky/engine/core/dom/Attr.h"
 #include "sky/engine/core/dom/Attribute.h"
 #include "sky/engine/wtf/Vector.h"
 
 namespace blink {
 
 template <typename Container, typename ContainerMemberType = Container>
 class AttributeCollectionGeneric {
 public:
@@ skipping 107 matching lines @@
     unsigned index = 0;
     for (iterator it = begin(); it != end; ++it, ++index) {
         if (it->localName() == attr->name())
             return index;
     }
     return kNotFound;
 }
 
 } // namespace blink
 
-#endif // AttributeCollection_h
+#endif  // SKY_ENGINE_CORE_DOM_ATTRIBUTECOLLECTION_H_