Make it possible to Crankshaft all kinds of stubs.

src/compiler.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 61 matching lines @@
     return LanguageModeField::decode(flags_);
   }
   bool is_in_loop() const { return IsInLoop::decode(flags_); }
   FunctionLiteral* function() const { return function_; }
   Scope* scope() const { return scope_; }
   Scope* global_scope() const { return global_scope_; }
   Handle<Code> code() const { return code_; }
   Handle<JSFunction> closure() const { return closure_; }
   Handle<SharedFunctionInfo> shared_info() const { return shared_info_; }
   Handle<Script> script() const { return script_; }
-  HydrogenCodeStub* code_stub() {return code_stub_; }
+  HydrogenCodeStub* code_stub() const {return code_stub_; }
   v8::Extension* extension() const { return extension_; }
   ScriptDataImpl* pre_parse_data() const { return pre_parse_data_; }
   Handle<Context> context() const { return context_; }
   BailoutId osr_ast_id() const { return osr_ast_id_; }
   int opt_count() const { return opt_count_; }
   int num_parameters() const;
   int num_heap_slots() const;
   Code::Flags flags() const;
 
   void MarkAsEval() {
@@ skipping 451 matching lines @@
 
   static void RecordFunctionCompilation(Logger::LogEventsAndTags tag,
                                         CompilationInfo* info,
                                         Handle<SharedFunctionInfo> shared);
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_COMPILER_H_