Revert r14252 as it broke --prof for some cases

src/profile-generator.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 876 matching lines @@
 void ProfileGenerator::RecordTickSample(const TickSample& sample) {
   // Allocate space for stack frames + pc + function + vm-state.
   ScopedVector<CodeEntry*> entries(sample.frames_count + 3);
   // As actual number of decoded code entries may vary, initialize
   // entries vector with NULL values.
   CodeEntry** entry = entries.start();
   memset(entry, 0, entries.length() * sizeof(*entry));
   if (sample.pc != NULL) {
     *entry++ = code_map_.FindEntry(sample.pc);
 
-    if (sample.external_callback) {
+    if (sample.has_external_callback) {
       // Don't use PC when in external callback code, as it can point
       // inside callback's code, and we will erroneously report
       // that a callback calls itself.
       *(entries.start()) = NULL;
       *entry++ = code_map_.FindEntry(sample.external_callback);
     }
 
     for (const Address* stack_pos = sample.stack,
            *stack_end = stack_pos + sample.frames_count;
          stack_pos != stack_end;
@@ skipping 14 matching lines @@
     if (no_symbolized_entries) {
       *entry++ = EntryForVMState(sample.state);
     }
   }
 
   profiles_->AddPathToCurrentProfiles(entries);
 }
 
 
 } }  // namespace v8::internal