Remove the HValueOf instruction.

src/x64/lithium-x64.cc

Index: src/x64/lithium-x64.cc
diff --git a/src/x64/lithium-x64.cc b/src/x64/lithium-x64.cc
index 5c3fd709800fbfdab1eb25c18ee8a54f6a3d56c5..f07cb3ba5e908e7046163e72cf6fafcaafee4995 100644
--- a/src/x64/lithium-x64.cc
+++ b/src/x64/lithium-x64.cc
@@ -1612,13 +1612,6 @@ LInstruction* LChunkBuilder::DoElementsKind(HElementsKind* instr) {
 }
 
 
-LInstruction* LChunkBuilder::DoValueOf(HValueOf* instr) {
-  LOperand* object = UseRegister(instr->value());
-  LValueOf* result = new(zone()) LValueOf(object);
-  return DefineSameAsFirst(result);
-}
-
-
 LInstruction* LChunkBuilder::DoDateField(HDateField* instr) {
   LOperand* object = UseFixed(instr->value(), rax);
   LDateField* result = new(zone()) LDateField(object, instr->index());