diff --git a/src/factory.cc b/src/factory.cc
index d3a69744d2..d4909a7c1b 100644
--- a/src/factory.cc
+++ b/src/factory.cc
@@ -287,6 +287,14 @@ MaybeHandle<SeqTwoByteString> Factory::NewRawTwoByteString(
 }
 
 
+Handle<String> Factory::LookupSingleCharacterStringFromCode(uint32_t index) {
+  CALL_HEAP_FUNCTION(
+      isolate(),
+      isolate()->heap()->LookupSingleCharacterStringFromCode(index),
+      String);
+}
+
+
 // Returns true for a character in a range.  Both limits are inclusive.
 static inline bool Between(uint32_t character, uint32_t from, uint32_t to) {
   // This makes uses of the the unsigned wraparound.
@@ -469,7 +477,7 @@ Handle<String> Factory::NewProperSubString(Handle<String> str,
   int length = end - begin;
   if (length <= 0) return empty_string();
   if (length == 1) {
-    return LookupSingleCharacterStringFromCode(isolate(), str->Get(begin));
+    return LookupSingleCharacterStringFromCode(str->Get(begin));
   }
   if (length == 2) {
     // Optimization for 2-byte strings often used as keys in a decompression
diff --git a/src/factory.h b/src/factory.h
index c1b7ba7251..53f55d3aac 100644
--- a/src/factory.h
+++ b/src/factory.h
@@ -142,6 +142,8 @@ class Factory V8_FINAL {
       int length,
       PretenureFlag pretenure = NOT_TENURED);
 
+  Handle<String> LookupSingleCharacterStringFromCode(uint32_t index);
+
   // Create a new cons string object which consists of a pair of strings.
   MUST_USE_RESULT MaybeHandle<String> NewConsString(Handle<String> left,
                                                     Handle<String> right);
diff --git a/src/handles.cc b/src/handles.cc
index b3052ad6a8..7ed7c8e80f 100644
--- a/src/handles.cc
+++ b/src/handles.cc
@@ -179,15 +179,6 @@ Handle<Object> GetProperty(Handle<JSReceiver> obj,
 }
 
 
-Handle<String> LookupSingleCharacterStringFromCode(Isolate* isolate,
-                                                   uint32_t index) {
-  CALL_HEAP_FUNCTION(
-      isolate,
-      isolate->heap()->LookupSingleCharacterStringFromCode(index),
-      String);
-}
-
-
 // Wrappers for scripts are kept alive and cached in weak global
 // handles referred from foreign objects held by the scripts as long as
 // they are used. When they are not used anymore, the garbage
diff --git a/src/handles.h b/src/handles.h
index 3f60404212..edeb27b510 100644
--- a/src/handles.h
+++ b/src/handles.h
@@ -302,9 +302,6 @@ Handle<Object> HasProperty(Handle<JSReceiver> obj, Handle<Object> key);
 
 Handle<Object> GetProperty(Handle<JSReceiver> obj, const char* name);
 
-Handle<String> LookupSingleCharacterStringFromCode(Isolate* isolate,
-                                                   uint32_t index);
-
 // Get the JS object corresponding to the given script; create it
 // if none exists.
 Handle<JSValue> GetScriptWrapper(Handle<Script> script);
diff --git a/src/hydrogen-instructions.cc b/src/hydrogen-instructions.cc
index b54656c075..4f728c6f7b 100644
--- a/src/hydrogen-instructions.cc
+++ b/src/hydrogen-instructions.cc
@@ -4097,7 +4097,7 @@ HInstruction* HStringCharFromCode::New(
       if (std::isfinite(c_code->DoubleValue())) {
         uint32_t code = c_code->NumberValueAsInteger32() & 0xffff;
         return HConstant::New(zone, context,
-            LookupSingleCharacterStringFromCode(isolate, code));
+            isolate->factory()->LookupSingleCharacterStringFromCode(code));
       }
       return HConstant::New(zone, context, isolate->factory()->empty_string());
     }
diff --git a/src/json-parser.h b/src/json-parser.h
index a566402c73..5d67ae2a9a 100644
--- a/src/json-parser.h
+++ b/src/json-parser.h
@@ -257,8 +257,7 @@ MaybeHandle<Object> JsonParser<seq_ascii>::ParseJson() {
         break;
       default:
         message = "unexpected_token";
-        Handle<Object> name =
-            LookupSingleCharacterStringFromCode(isolate_, c0_);
+        Handle<Object> name = factory->LookupSingleCharacterStringFromCode(c0_);
         Handle<FixedArray> element = factory->NewFixedArray(1);
         element->set(0, *name);
         array = factory->NewJSArrayWithElements(element);
diff --git a/src/runtime.cc b/src/runtime.cc
index c659936d74..9e8a53ef27 100644
--- a/src/runtime.cc
+++ b/src/runtime.cc
@@ -3237,16 +3237,6 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_ObjectFreeze) {
 }
 
 
-MUST_USE_RESULT static MaybeObject* CharFromCode(Isolate* isolate,
-                                                 Object* char_code) {
-  if (char_code->IsNumber()) {
-    return isolate->heap()->LookupSingleCharacterStringFromCode(
-        NumberToUint32(char_code) & 0xffff);
-  }
-  return isolate->heap()->empty_string();
-}
-
-
 RUNTIME_FUNCTION(MaybeObject*, RuntimeHidden_StringCharCodeAt) {
   SealHandleScope shs(isolate);
   ASSERT(args.length() == 2);
@@ -3272,9 +3262,13 @@ RUNTIME_FUNCTION(MaybeObject*, RuntimeHidden_StringCharCodeAt) {
 
 
 RUNTIME_FUNCTION(MaybeObject*, Runtime_CharFromCode) {
-  SealHandleScope shs(isolate);
+  HandleScope handlescope(isolate);
   ASSERT(args.length() == 1);
-  return CharFromCode(isolate, args[0]);
+  if (args[0]->IsNumber()) {
+    uint32_t code = NumberToUint32(args[0]) & 0xffff;
+    return *isolate->factory()->LookupSingleCharacterStringFromCode(code);
+  }
+  return isolate->heap()->empty_string();
 }
 
 
@@ -4883,8 +4877,7 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_IsValidSmi) {
 static Handle<Object> GetCharAt(Handle<String> string, uint32_t index) {
   if (index < static_cast<uint32_t>(string->length())) {
     string->TryFlatten();
-    return LookupSingleCharacterStringFromCode(
-        string->GetIsolate(),
+    return string->GetIsolate()->factory()->LookupSingleCharacterStringFromCode(
         string->Get(index));
   }
   return Execution::CharAt(string, index);
@@ -6854,7 +6847,7 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_StringToArray) {
   }
   for (int i = position; i < length; ++i) {
     Handle<Object> str =
-        LookupSingleCharacterStringFromCode(isolate, s->Get(i));
+        isolate->factory()->LookupSingleCharacterStringFromCode(s->Get(i));
     elements->set(i, *str);
   }