Added sqrt and pow for arm and x64 - to fix build failures.

src/arm/codegen-arm.h

Index: src/arm/codegen-arm.h
===================================================================
--- src/arm/codegen-arm.h	(revision 4053)
+++ src/arm/codegen-arm.h	(working copy)
@@ -397,12 +397,15 @@
   void GenerateNumberToString(ZoneList<Expression*>* args);
 
   // Fast support for Math.pow().
-  void GeneratePow(ZoneList<Expression*>* args);
+  void GenerateMathPow(ZoneList<Expression*>* args);
 
   // Fast call to sine function.
   void GenerateMathSin(ZoneList<Expression*>* args);
   void GenerateMathCos(ZoneList<Expression*>* args);
 
+  // Fast support for Math.pow().
+  void GenerateMathSqrt(ZoneList<Expression*>* args);
+
   // Simple condition analysis.
   enum ConditionAnalysis {
     ALWAYS_TRUE,