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

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

Index: src/compiler-dispatcher/compiler-dispatcher-job.h
diff --git a/src/compiler-dispatcher/compiler-dispatcher-job.h b/src/compiler-dispatcher/compiler-dispatcher-job.h
index a1a6c3f4d017513bce5d3718bd050af49147c058..b36dbc7fc22a65fc21d917168a36f81719560ef1 100644
--- a/src/compiler-dispatcher/compiler-dispatcher-job.h
+++ b/src/compiler-dispatcher/compiler-dispatcher-job.h
@@ -28,7 +28,6 @@ class SharedFunctionInfo;
 class String;
 class UnicodeCache;
 class Utf16CharacterStream;
-class Zone;
 
 enum class CompileJobStatus {
   kInitial,