Fix sky include guards to match Chromium style

sky/engine/wtf/PageAllocator.h

 /*
  * Copyright (C) 2013 Google Inc. 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
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 10 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 WTF_PageAllocator_h
-#define WTF_PageAllocator_h
+#ifndef SKY_ENGINE_WTF_PAGEALLOCATOR_H_
+#define SKY_ENGINE_WTF_PAGEALLOCATOR_H_
 
 #include <stdint.h>
 #include "sky/engine/wtf/Assertions.h"
 #include "sky/engine/wtf/CPU.h"
 #include "sky/engine/wtf/WTFExport.h"
 
 namespace WTF {
 
 #if OS(WIN)
 static const size_t kPageAllocationGranularityShift = 16; // 64KB
@@ skipping 49 matching lines @@
 WTF_EXPORT void decommitSystemPages(void* addr, size_t len);
 
 // Recommit one or more system pages. Decommitted system pages must be
 // recommitted before they are read are written again.
 // Note that this operation may be a no-op on some platforms.
 // len must be a multiple of kSystemPageSize bytes.
 WTF_EXPORT void recommitSystemPages(void* addr, size_t len);
 
 } // namespace WTF
 
-#endif // WTF_PageAllocator_h
+#endif  // SKY_ENGINE_WTF_PAGEALLOCATOR_H_