[Compiler] Enable use of seperate zones for parsing and compiling.

src/compiler-dispatcher/compiler-dispatcher-job.h

 // Copyright 2016 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_COMPILER_DISPATCHER_COMPILER_DISPATCHER_JOB_H_
 #define V8_COMPILER_DISPATCHER_COMPILER_DISPATCHER_JOB_H_
 
 #include <memory>
 
 #include "include/v8.h"
@@ skipping 10 matching lines @@
 class CompilationInfo;
 class CompilationJob;
 class FunctionLiteral;
 class Isolate;
 class ParseInfo;
 class Parser;
 class SharedFunctionInfo;
 class String;
 class UnicodeCache;
 class Utf16CharacterStream;
-class Zone;
 
 enum class CompileJobStatus {
   kInitial,
   kReadyToParse,
   kParsed,
   kReadyToAnalyze,
   kAnalyzed,
   kReadyToCompile,
   kCompiled,
   kFailed,
@@ skipping 78 matching lines @@
 
   bool trace_compiler_dispatcher_jobs_;
 
   DISALLOW_COPY_AND_ASSIGN(CompilerDispatcherJob);
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_DISPATCHER_COMPILER_DISPATCHER_JOB_H_