Fix object initialization when slack tracking for it's map is still enabled.

src/mips64/macro-assembler-mips64.h

Index: src/mips64/macro-assembler-mips64.h
diff --git a/src/mips64/macro-assembler-mips64.h b/src/mips64/macro-assembler-mips64.h
index 0e88ca4d6d68f91cc5f38f9f0d484eb05a8c0436..aa61941e16ebf1a5f052ee29ad7f508d6454630c 100644
--- a/src/mips64/macro-assembler-mips64.h
+++ b/src/mips64/macro-assembler-mips64.h
@@ -564,12 +564,8 @@ class MacroAssembler: public Assembler {
                 Label* gc_required,
                 AllocationFlags flags);
 
-  void Allocate(Register object_size,
-                Register result,
-                Register scratch1,
-                Register scratch2,
-                Label* gc_required,
-                AllocationFlags flags);
+  void Allocate(Register object_size, Register result, Register result_end,
+                Register scratch, Label* gc_required, AllocationFlags flags);
 
   void AllocateTwoByteString(Register result,
                              Register length,