Always include debugger support.

src/arm64/macro-assembler-arm64.h

 // Copyright 2013 the V8 project authors. 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
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1260 matching lines @@
       masm_->use_real_aborts_ = false;
     }
     ~NoUseRealAbortsScope() {
       masm_->use_real_aborts_ = saved_;
     }
    private:
     bool saved_;
     MacroAssembler* masm_;
   };
 
-#ifdef ENABLE_DEBUGGER_SUPPORT
   // ---------------------------------------------------------------------------
   // Debugger Support
 
   void DebugBreak();
-#endif
+
   // ---------------------------------------------------------------------------
   // Exception handling
 
   // Push a new try handler and link into try handler chain.
   void PushTryHandler(StackHandler::Kind kind, int handler_index);
 
   // Unlink the stack handler on top of the stack from the try handler chain.
   // Must preserve the result register.
   void PopTryHandler();
 
@@ skipping 1011 matching lines @@
 #error "Unsupported option"
 #define CODE_COVERAGE_STRINGIFY(x) #x
 #define CODE_COVERAGE_TOSTRING(x) CODE_COVERAGE_STRINGIFY(x)
 #define __FILE_LINE__ __FILE__ ":" CODE_COVERAGE_TOSTRING(__LINE__)
 #define ACCESS_MASM(masm) masm->stop(__FILE_LINE__); masm->
 #else
 #define ACCESS_MASM(masm) masm->
 #endif
 
 #endif  // V8_ARM64_MACRO_ASSEMBLER_ARM64_H_