Reland: [Parse] ParseInfo owns the parsing Zone.

src/background-parsing-task.h

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_BACKGROUND_PARSING_TASK_H_
 #define V8_BACKGROUND_PARSING_TASK_H_
 
 #include <memory>
 
 #include "include/v8.h"
@@ skipping 20 matching lines @@
 
   // Internal implementation of v8::ScriptCompiler::StreamedSource.
   std::unique_ptr<ScriptCompiler::ExternalSourceStream> source_stream;
   ScriptCompiler::StreamedSource::Encoding encoding;
   std::unique_ptr<ScriptCompiler::CachedData> cached_data;
 
   // Data needed for parsing, and data needed to to be passed between thread
   // between parsing and compilation. These need to be initialized before the
   // compilation starts.
   UnicodeCache unicode_cache;
-  std::unique_ptr<Zone> zone;
   std::unique_ptr<ParseInfo> info;
   std::unique_ptr<Parser> parser;
 
   // Prevent copying.
   StreamedSource(const StreamedSource&) = delete;
   StreamedSource& operator=(const StreamedSource&) = delete;
 };
 
 
 class BackgroundParsingTask : public ScriptCompiler::ScriptStreamingTask {
  public:
   BackgroundParsingTask(StreamedSource* source,
                         ScriptCompiler::CompileOptions options, int stack_size,
                         Isolate* isolate);
 
   virtual void Run();
 
  private:
   StreamedSource* source_;  // Not owned.
   int stack_size_;
   ScriptData* script_data_;
 };
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_BACKGROUND_PARSING_TASK_H_