Fix sky include guards to match Chromium style

sky/engine/wtf/SpinLock.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_SpinLock_h
-#define WTF_SpinLock_h
+#ifndef SKY_ENGINE_WTF_SPINLOCK_H_
+#define SKY_ENGINE_WTF_SPINLOCK_H_
 
 // DESCRIPTION
 // spinLockLock() and spinLockUnlock() are simple spinlock primitives based on
 // the standard CPU primitive of atomic increment and decrement of an int at
 // a given memory address.
 
 #include "sky/engine/wtf/Atomics.h"
 
 namespace WTF {
 
 ALWAYS_INLINE void spinLockLock(int volatile* lock)
 {
     while (UNLIKELY(atomicTestAndSetToOne(lock))) {
         while (*lock) { } // Spin without spamming locked instructions.
     }
 }
 
 ALWAYS_INLINE void spinLockUnlock(int volatile* lock)
 {
     atomicSetOneToZero(lock);
 }
 
 } // namespace WTF
 
 using WTF::spinLockLock;
 using WTF::spinLockUnlock;
 
-#endif // WTF_SpinLock_h
+#endif  // SKY_ENGINE_WTF_SPINLOCK_H_