StringTable::LookupKey() and all callers handlified.

src/heap.h

Index: src/heap.h
diff --git a/src/heap.h b/src/heap.h
index c44d99edbf0c00cef1287c65d5a1b481ec5bfb5c..ac6352273ab8bd0c53fba6c4f5909af2c84ec013 100644
--- a/src/heap.h
+++ b/src/heap.h
@@ -828,13 +828,6 @@ class Heap {
   MUST_USE_RESULT MaybeObject* AllocateInternalizedStringImpl(
       T t, int chars, uint32_t hash_field);
 
-  // Computes a single character string where the character has code.
-  // A cache is used for ASCII codes.
-  // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation
-  // failed. Please note this does not perform a garbage collection.
-  MUST_USE_RESULT MaybeObject* LookupSingleCharacterStringFromCode(
-      uint16_t code);
-
   // Allocate a byte array of the specified length
   // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation
   // failed.
@@ -1005,12 +998,6 @@ class Heap {
   // Returns Failure::RetryAfterGC(requested_bytes, space) if allocation
   // failed.
   // Please note this function does not perform a garbage collection.
-  MUST_USE_RESULT MaybeObject* InternalizeUtf8String(const char* str) {
-    return InternalizeUtf8String(CStrVector(str));
-  }
-  MUST_USE_RESULT MaybeObject* InternalizeUtf8String(Vector<const char> str);
-
-  MUST_USE_RESULT MaybeObject* InternalizeString(String* str);
   MUST_USE_RESULT MaybeObject* InternalizeStringWithKey(HashTableKey* key);
 
   bool InternalizeStringIfExists(String* str, String** result);