Revert of Fix compiler warnings on "make android_arm"

src/compiler/js-operator.cc

Index: src/compiler/js-operator.cc
diff --git a/src/compiler/js-operator.cc b/src/compiler/js-operator.cc
index f4f62ac55e8bdbc6b600840631d60ff83588d0f7..d19bb767b4a42fe3a1287c6e53a7a69770d5b301 100644
--- a/src/compiler/js-operator.cc
+++ b/src/compiler/js-operator.cc
@@ -376,7 +376,7 @@
   return OpParameter<CreateLiteralParameters>(op);
 }
 
-BinaryOperationHint BinaryOperationHintOf(const Operator* op) {
+const BinaryOperationHint BinaryOperationHintOf(const Operator* op) {
   DCHECK(op->opcode() == IrOpcode::kJSBitwiseOr ||
          op->opcode() == IrOpcode::kJSBitwiseXor ||
          op->opcode() == IrOpcode::kJSBitwiseAnd ||
@@ -391,7 +391,7 @@
   return OpParameter<BinaryOperationHint>(op);
 }
 
-CompareOperationHint CompareOperationHintOf(const Operator* op) {
+const CompareOperationHint CompareOperationHintOf(const Operator* op) {
   DCHECK(op->opcode() == IrOpcode::kJSEqual ||
          op->opcode() == IrOpcode::kJSNotEqual ||
          op->opcode() == IrOpcode::kJSStrictEqual ||