Refactor JavaScriptFrame::function() to return a JSFunction* and remove associated casts.

src/compiler.cc

 // 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 547 matching lines @@
 
 #ifdef ENABLE_DEBUGGER_SUPPORT
   if (info->is_eval()) {
     Script::CompilationType compilation_type = Script::COMPILATION_TYPE_EVAL;
     script->set_compilation_type(Smi::FromInt(compilation_type));
     // For eval scripts add information on the function from which eval was
     // called.
     if (info->is_eval()) {
       StackTraceFrameIterator it(isolate);
       if (!it.done()) {
-        script->set_eval_from_shared(
-            JSFunction::cast(it.frame()->function())->shared());
+        script->set_eval_from_shared(it.frame()->function()->shared());
         Code* code = it.frame()->LookupCode();
         int offset = static_cast<int>(
             it.frame()->pc() - code->instruction_start());
         script->set_eval_from_instructions_offset(Smi::FromInt(offset));
       }
     }
   }
 
   // Notify debugger
   isolate->debugger()->OnBeforeCompile(script);
@@ skipping 668 matching lines @@
 
 
 bool CompilationPhase::ShouldProduceTraceOutput() const {
   // Produce trace output if flag is set so that the first letter of the
   // phase name matches the command line parameter FLAG_trace_phase.
   return (FLAG_trace_hydrogen &&
           OS::StrChr(const_cast<char*>(FLAG_trace_phase), name_[0]) != NULL);
 }
 
 } }  // namespace v8::internal