Compress sources of JS libraries in addition to the snapshot.

src/serialize.cc

Index: src/serialize.cc
diff --git a/src/serialize.cc b/src/serialize.cc
index a64fba309638ab9441328bbcf210cd63e55ab039..d960afde401c1cf958862183f915302ae085324e 100644
--- a/src/serialize.cc
+++ b/src/serialize.cc
@@ -1017,10 +1017,11 @@ void Deserializer::ReadChunk(Object** current,
 
       case kNativesStringResource: {
         int index = source_->Get();
-        Vector<const char> source_vector = Natives::GetScriptSource(index);
+        Vector<const char> source_vector = Natives::GetRawScriptSource(index);
         NativesExternalStringResource* resource =
-            new NativesExternalStringResource(
-                isolate->bootstrapper(), source_vector.start());
+            new NativesExternalStringResource(isolate->bootstrapper(),
+                                              source_vector.start(),
+                                              source_vector.length());
         *current++ = reinterpret_cast<Object*>(resource);
         break;
       }