Cleanup include guards:

src/regexp-macro-assembler-tracer.h

Index: src/regexp-macro-assembler-tracer.h
diff --git a/src/regexp-macro-assembler-tracer.h b/src/regexp-macro-assembler-tracer.h
index d3aeff73a5cbe615245d153a3c6781a092209a07..f25289e6e81b41ecd02c59606a196d5fb53f01fd 100644
--- a/src/regexp-macro-assembler-tracer.h
+++ b/src/regexp-macro-assembler-tracer.h
@@ -25,8 +25,8 @@
 // (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 REGEXP_MACRO_ASSEMBLER_TRACER_H_
-#define REGEXP_MACRO_ASSEMBLER_TRACER_H_
+#ifndef V8_REGEXP_MACRO_ASSEMBLER_TRACER_H_
+#define V8_REGEXP_MACRO_ASSEMBLER_TRACER_H_
 
 namespace v8 { namespace internal {
 
@@ -115,4 +115,4 @@ class RegExpMacroAssemblerTracer: public RegExpMacroAssembler {
 
 }}  // namespace v8::internal
 
-#endif  // REGEXP_MACRO_ASSEMBLER_TRACER_H_
+#endif  // V8_REGEXP_MACRO_ASSEMBLER_TRACER_H_