Convert all symbols accessor to return read only handles so that it is not necessary to create a ne…

vm/intermediate_language_x64.cc

Index: vm/intermediate_language_x64.cc
===================================================================
--- vm/intermediate_language_x64.cc	(revision 16583)
+++ vm/intermediate_language_x64.cc	(working copy)
@@ -378,7 +378,7 @@
     }
   } else {
     equality_ic_data = ICData::New(compiler->parsed_function().function(),
-                                   Symbols::EqualOperatorHandle(),
+                                   Symbols::EqualOperator(),
                                    deopt_id,
                                    kNumArgumentsChecked);
   }
@@ -1011,7 +1011,7 @@
   __ movq(result, Address(result,
                           char_code,
                           TIMES_HALF_WORD_SIZE,  // Char code is a smi.
-                          Symbols::kNullCharId * kWordSize));
+                          Symbols::kNullCharCodeSymbolOffset * kWordSize));
 }