Remove unused byte from Map::instance_sizes field.

src/mips64/macro-assembler-mips64.cc

Index: src/mips64/macro-assembler-mips64.cc
diff --git a/src/mips64/macro-assembler-mips64.cc b/src/mips64/macro-assembler-mips64.cc
index f7a77dd1b1d8d13744262af6f14117efb8b92555..8fc26d81793bc7fa3a03a911ecf3f9ebeae74d91 100644
--- a/src/mips64/macro-assembler-mips64.cc
+++ b/src/mips64/macro-assembler-mips64.cc
@@ -3569,26 +3569,6 @@ void MacroAssembler::Allocate(Register object_size,
 }
 
 
-void MacroAssembler::UndoAllocationInNewSpace(Register object,
-                                              Register scratch) {
-  ExternalReference new_space_allocation_top =
-      ExternalReference::new_space_allocation_top_address(isolate());
-
-  // Make sure the object has no tag before resetting top.
-  And(object, object, Operand(~kHeapObjectTagMask));
-#ifdef DEBUG
-  // Check that the object un-allocated is below the current top.
-  li(scratch, Operand(new_space_allocation_top));
-  ld(scratch, MemOperand(scratch));
-  Check(less, kUndoAllocationOfNonAllocatedMemory,
-      object, Operand(scratch));
-#endif
-  // Write the address of the object to un-allocate as the current top.
-  li(scratch, Operand(new_space_allocation_top));
-  sd(object, MemOperand(scratch));
-}
-
-
 void MacroAssembler::AllocateTwoByteString(Register result,
                                            Register length,
                                            Register scratch1,