Add new HSeqStringGetChar 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 d90736a1673f3c35761ee81502455c9aec137035..51e3220c9fe897db10e0cea96771862ade0574b7 100644
--- a/src/x64/lithium-x64.cc
+++ b/src/x64/lithium-x64.cc
@@ -1756,6 +1756,13 @@ LInstruction* LChunkBuilder::DoDateField(HDateField* instr) {
 }
 
 
+LInstruction* LChunkBuilder::DoSeqStringGetChar(HSeqStringGetChar* instr) {
+  LOperand* string = UseRegisterAtStart(instr->string());
+  LOperand* index = UseRegisterOrConstantAtStart(instr->index());
+  return DefineAsRegister(new(zone()) LSeqStringGetChar(string, index));
+}
+
+
 LInstruction* LChunkBuilder::DoSeqStringSetChar(HSeqStringSetChar* instr) {
   LOperand* string = UseRegisterAtStart(instr->string());
   LOperand* index = UseRegisterOrConstantAtStart(instr->index());