ARM: Makefile/gyp update allowing better control of ARM specific options.

src/arm/macro-assembler-arm.h

Index: src/arm/macro-assembler-arm.h
diff --git a/src/arm/macro-assembler-arm.h b/src/arm/macro-assembler-arm.h
index fc6d7978e59509f2452d721aa4d913df5172e315..86ae8f22d958e993259bc2cd25bbf006fd8f7394 100644
--- a/src/arm/macro-assembler-arm.h
+++ b/src/arm/macro-assembler-arm.h
@@ -1149,7 +1149,9 @@ class MacroAssembler: public Assembler {
 
   // EABI variant for double arguments in use.
   bool use_eabi_hardfloat() {
-#if USE_EABI_HARDFLOAT
+#ifdef __arm__
+    return OS::ArmUsingHardFloat();
+#elif USE_EABI_HARDFLOAT
     return true;
 #else
     return false;