Upgrade V8 to 5.1.281.57  DO NOT MERGE

FPIIM-449

Change-Id: Id981b686b4d587ac31697662eb98bb34be42ad90
(cherry picked from commit 3b9bc31999c9787eb726ecdbfd5796bfdec32a18)
diff --git a/src/compiler/simplified-operator.h b/src/compiler/simplified-operator.h
index 2ed4b5f..a39d864 100644
--- a/src/compiler/simplified-operator.h
+++ b/src/compiler/simplified-operator.h
@@ -143,6 +143,12 @@
   const Operator* NumberShiftLeft();
   const Operator* NumberShiftRight();
   const Operator* NumberShiftRightLogical();
+  const Operator* NumberImul();
+  const Operator* NumberClz32();
+  const Operator* NumberCeil();
+  const Operator* NumberFloor();
+  const Operator* NumberRound();
+  const Operator* NumberTrunc();
   const Operator* NumberToInt32();
   const Operator* NumberToUint32();
   const Operator* NumberIsHoleNaN();
@@ -154,6 +160,7 @@
   const Operator* StringEqual();
   const Operator* StringLessThan();
   const Operator* StringLessThanOrEqual();
+  const Operator* StringToNumber();
 
   const Operator* ChangeTaggedToInt32();
   const Operator* ChangeTaggedToUint32();
@@ -167,6 +174,7 @@
   const Operator* ObjectIsNumber();
   const Operator* ObjectIsReceiver();
   const Operator* ObjectIsSmi();
+  const Operator* ObjectIsUndetectable();
 
   const Operator* Allocate(PretenureFlag pretenure = NOT_TENURED);