Changing the aging mechanism for script and eval caches.

src/compilation-cache.h

Index: src/compilation-cache.h
diff --git a/src/compilation-cache.h b/src/compilation-cache.h
index 6799b1cb91c735fb6c8a1aa023dea8acfe6e315d..a7c84b7b5d1b3bc51104635bc1f834e3c980ad6b 100644
--- a/src/compilation-cache.h
+++ b/src/compilation-cache.h
@@ -89,9 +89,6 @@ class CompilationCacheScript : public CompilationSubCache {
                  int column_offset,
                  bool is_shared_cross_origin);
 
-  void* script_histogram_;
-  bool script_histogram_initialized_;
-
   DISALLOW_IMPLICIT_CONSTRUCTORS(CompilationCacheScript);
 };