Re-revert "Flush parallel recompilation queues on context dispose notification" (r15883).

src/debug.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 2026 matching lines @@
   void VisitThread(Isolate* isolate, ThreadLocalTop* top) {
     RedirectActivationsToRecompiledCodeOnThread(isolate, top);
   }
 };
 
 
 void Debug::PrepareForBreakPoints() {
   // If preparing for the first break point make sure to deoptimize all
   // functions as debugging does not work with optimized code.
   if (!has_break_points_) {
-    if (FLAG_parallel_recompilation) {
-      isolate_->optimizing_compiler_thread()->Flush();
-    }
-
     Deoptimizer::DeoptimizeAll(isolate_);
 
     Handle<Code> lazy_compile =
         Handle<Code>(isolate_->builtins()->builtin(Builtins::kLazyCompile));
 
     // There will be at least one break point when we are done.
     has_break_points_ = true;
 
     // Keep the list of activated functions in a handlified list as it
     // is used both in GC and non-GC code.
@@ skipping 1801 matching lines @@
     {
       Locker locker(reinterpret_cast<v8::Isolate*>(isolate_));
       isolate_->debugger()->CallMessageDispatchHandler();
     }
   }
 }
 
 #endif  // ENABLE_DEBUGGER_SUPPORT
 
 } }  // namespace v8::internal