Compress sources of JS libraries in addition to the snapshot.

src/natives.h

Index: src/natives.h
diff --git a/src/natives.h b/src/natives.h
index ce90eac24878a6004db09bc1e35c67e0a6d2e3db..bca1544939fd36d02a96cce97ce98865383cac19 100644
--- a/src/natives.h
+++ b/src/natives.h
@@ -52,8 +52,11 @@ class NativesCollection {
   // non-debugger scripts have an index in the interval [GetDebuggerCount(),
   // GetNativesCount()).
   static int GetIndex(const char* name);
-  static Vector<const char> GetScriptSource(int index);
+  static int GetRawScriptSize(int index);
+  static Vector<const char> GetRawScriptSource(int index);
   static Vector<const char> GetScriptName(int index);
+  static Vector<const byte> GetScriptSource(int index);
+  static void SetRawScriptSource(int index, Vector<const char> raw_source);
 };
 
 typedef NativesCollection<CORE> Natives;