[debugger] fix step-next for tail calls.

src/mips64/assembler-mips64.cc

 // Copyright (c) 1994-2006 Sun Microsystems 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.
 //
@@ skipping 3201 matching lines @@
   }
   RecordRelocInfo(RelocInfo::INTERNAL_REFERENCE);
   EmitHelper(data);
 }
 
 
 void Assembler::RecordRelocInfo(RelocInfo::Mode rmode, intptr_t data) {
   // We do not try to reuse pool constants.
   RelocInfo rinfo(isolate(), pc_, rmode, data, NULL);
   if (rmode >= RelocInfo::COMMENT &&
-      rmode <= RelocInfo::DEBUG_BREAK_SLOT_AT_CALL) {
+      rmode <= RelocInfo::DEBUG_BREAK_SLOT_AT_TAIL_CALL) {
     // Adjust code for new modes.
     DCHECK(RelocInfo::IsDebugBreakSlot(rmode)
            || RelocInfo::IsComment(rmode)
            || RelocInfo::IsPosition(rmode));
     // These modes do not need an entry in the constant pool.
   }
   if (!RelocInfo::IsNone(rinfo.rmode())) {
     // Don't record external references unless the heap will be serialized.
     if (rmode == RelocInfo::EXTERNAL_REFERENCE &&
         !serializer_enabled() && !emit_debug_code()) {
@@ skipping 159 matching lines @@
   if (icache_flush_mode != SKIP_ICACHE_FLUSH) {
     Assembler::FlushICache(isolate, pc, 4 * Assembler::kInstrSize);
   }
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_MIPS64