Revert of [es2015] Precompute the descriptive string for symbols.

src/factory.cc

Index: src/factory.cc
diff --git a/src/factory.cc b/src/factory.cc
index 9c73a519ae0512cbb6284c89395d55f47b116464..3948eec3a722461b50bfdc241322fedb837f6060 100644
--- a/src/factory.cc
+++ b/src/factory.cc
@@ -16,7 +16,6 @@
 #include "src/objects/frame-array-inl.h"
 #include "src/objects/module-info.h"
 #include "src/objects/scope-info.h"
-#include "src/string-builder.h"
 
 namespace v8 {
 namespace internal {
@@ -910,38 +909,9 @@
       Symbol);
 }
 
-MaybeHandle<Symbol> Factory::NewSymbol(Handle<Object> name) {
-  DCHECK(name->IsString() || name->IsUndefined(isolate()));
-  Handle<Symbol> symbol = NewSymbol();
-  if (name->IsString()) {
-    // Compute the descriptive string for the {symbol}.
-    Handle<String> descriptive_string;
-    IncrementalStringBuilder builder(isolate());
-    builder.AppendCString("Symbol(");
-    builder.AppendString(Handle<String>::cast(name));
-    builder.AppendCharacter(')');
-    ASSIGN_RETURN_ON_EXCEPTION(isolate(), descriptive_string, builder.Finish(),
-                               Symbol);
-
-    // Make sure those strings are flattened.
-    name = String::Flatten(Handle<String>::cast(name), TENURED);
-    descriptive_string = String::Flatten(descriptive_string, TENURED);
-
-    symbol->set_name(String::cast(*name));
-    symbol->set_descriptive_string(*descriptive_string);
-  }
-  return symbol;
-}
 
 Handle<Symbol> Factory::NewPrivateSymbol() {
   Handle<Symbol> symbol = NewSymbol();
-  symbol->set_is_private(true);
-  return symbol;
-}
-
-MaybeHandle<Symbol> Factory::NewPrivateSymbol(Handle<Object> name) {
-  Handle<Symbol> symbol;
-  ASSIGN_RETURN_ON_EXCEPTION(isolate(), symbol, NewSymbol(name), Symbol);
   symbol->set_is_private(true);
   return symbol;
 }