Allow the optimizing code generator to call Math.pow with untagged doubles.

src/objects.h

Index: src/objects.h
===================================================================
--- src/objects.h	(revision 5948)
+++ src/objects.h	(working copy)
@@ -3729,7 +3729,9 @@
   kMathACos = 0xa,
   kMathATan = 0xb,
   kMathExp = 0xc,
-  kMathSqrt = 0xd
+  kMathSqrt = 0xd,
+  kMathPow = 0xe,
+  kMathPowHalf = 0xf
 };
 
 
@@ -4154,11 +4156,11 @@
   static const int kTryFullCodegen = 1;
   static const int kAllowLazyCompilation = 2;
   static const int kMathFunctionShift = 3;
-  static const int kMathFunctionMask = 0xf;
-  static const int kLiveObjectsMayExist = 7;
-  static const int kCodeAgeShift = 8;
+  static const int kMathFunctionMask = 0x1f;
+  static const int kLiveObjectsMayExist = 8;
+  static const int kCodeAgeShift = 9;
   static const int kCodeAgeMask = 0x7;
-  static const int kOptimizationDisabled = 11;
+  static const int kOptimizationDisabled = 12;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(SharedFunctionInfo);
 };