[async-iteration] implement Async-from-Sync Iterator

src/compiler/code-assembler.cc

Index: src/compiler/code-assembler.cc
diff --git a/src/compiler/code-assembler.cc b/src/compiler/code-assembler.cc
index e258866bbef67356ed8d5d612f9e9d702e607ac5..1ace7dae5e262764a6a9519fe8904556ed0e9966 100644
--- a/src/compiler/code-assembler.cc
+++ b/src/compiler/code-assembler.cc
@@ -188,6 +188,10 @@ Node* CodeAssembler::HeapConstant(Handle<HeapObject> object) {
   return raw_assembler()->HeapConstant(object);
 }
 
+Node* CodeAssembler::CStringConstant(const char* str) {
+  return HeapConstant(factory()->NewStringFromAsciiChecked(str, TENURED));
+}
+
 Node* CodeAssembler::BooleanConstant(bool value) {
   return raw_assembler()->BooleanConstant(value);
 }