Remove some dead code in src/objects.cc

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index 45748500939bbd7ee82cdec3b3bb621dcd5c6303..ca5f709813e32064d76dc29092f5e73057fea6e2 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -1915,9 +1915,6 @@ class JSReceiver: public HeapObject {
 
   MUST_USE_RESULT static Maybe<bool> IsExtensible(Handle<JSReceiver> object);
 
-  // Tests for the fast common case for property enumeration.
-  bool IsSimpleEnum();
-
   // Returns the class name ([[Class]] property in the specification).
   String* class_name();
 
@@ -7905,7 +7902,6 @@ class JSRegExp: public JSObject {
   DECL_ACCESSORS(source, Object)
 
   static MaybeHandle<JSRegExp> New(Handle<String> source, Flags flags);
-  static MaybeHandle<JSRegExp> New(Handle<String> source, Handle<String> flags);
   static Handle<JSRegExp> Copy(Handle<JSRegExp> regexp);
 
   static MaybeHandle<JSRegExp> Initialize(Handle<JSRegExp> regexp,
@@ -8849,15 +8845,6 @@ class String: public Name {
       RobustnessFlag robustness_flag = FAST_STRING_TRAVERSAL,
       int* length_output = 0);
 
-  // Return a 16 bit Unicode representation of the string.
-  // The string should be nearly flat, otherwise the performance of
-  // of this method may be very bad.  Setting robustness_flag to
-  // ROBUST_STRING_TRAVERSAL invokes behaviour that is robust  This means it
-  // handles unexpected data without causing assert failures and it does not
-  // do any heap allocations.  This is useful when printing stack traces.
-  base::SmartArrayPointer<uc16> ToWideCString(
-      RobustnessFlag robustness_flag = FAST_STRING_TRAVERSAL);
-
   bool ComputeArrayIndex(uint32_t* index);
 
   // Externalization.