Enable preaging of code objects when --optimize-for-size.

src/arm/lithium-codegen-arm.cc

Index: src/arm/lithium-codegen-arm.cc
diff --git a/src/arm/lithium-codegen-arm.cc b/src/arm/lithium-codegen-arm.cc
index 059aa13322adb4dde769c9be9cf594fac8133cb4..95c9069e0c7030d398b1451f966cbf8f129600f2 100644
--- a/src/arm/lithium-codegen-arm.cc
+++ b/src/arm/lithium-codegen-arm.cc
@@ -162,7 +162,9 @@ bool LCodeGen::GeneratePrologue() {
       // The following three instructions must remain together and unmodified
       // for code aging to work properly.
       __ stm(db_w, sp, r1.bit() | cp.bit() | fp.bit() | lr.bit());
-      __ nop(ip.code());
+      // Pre-age code objects on low memory devices.
+      __ nop(isolate()->is_memory_constrained() ?
+             kPreAgeCodeNopType : kNoAgeCodeNopType);
       // Adjust FP to point to saved FP.
       __ add(fp, sp, Operand(2 * kPointerSize));
     }