MIPS: Remove all uses of field-tracking flags that do not make decisions but are subject to existin…

src/mips/lithium-codegen-mips.cc

Index: src/mips/lithium-codegen-mips.cc
diff --git a/src/mips/lithium-codegen-mips.cc b/src/mips/lithium-codegen-mips.cc
index 30d7efd1b0d2f89034346ada2d66a9ab13ca19be..f4c3a4db11daea9b55357f49ac8701c36b381e8f 100644
--- a/src/mips/lithium-codegen-mips.cc
+++ b/src/mips/lithium-codegen-mips.cc
@@ -3987,7 +3987,7 @@ void LCodeGen::DoStoreNamedField(LStoreNamedField* instr) {
       instr->hydrogen()->value()->IsHeapObject()
           ? OMIT_SMI_CHECK : INLINE_SMI_CHECK;
 
-  if (FLAG_track_heap_object_fields && representation.IsHeapObject()) {
+  if (representation.IsHeapObject()) {
     Register value = ToRegister(instr->value());
     if (!instr->hydrogen()->value()->type().IsHeapObject()) {
       __ SmiTst(value, scratch);