Use a different map to distinguish eval contexts

src/factory.h

Index: src/factory.h
diff --git a/src/factory.h b/src/factory.h
index b32db7a255f9b7a5df6b5d934550d5d15141be29..ac404e6cc0dd043fed5e8ec325bdf3ded09051c4 100644
--- a/src/factory.h
+++ b/src/factory.h
@@ -296,8 +296,9 @@ class V8_EXPORT_PRIVATE Factory final {
                                    Handle<JSFunction> function,
                                    Handle<ScopeInfo> scope_info);
 
-  // Create a function context.
-  Handle<Context> NewFunctionContext(int length, Handle<JSFunction> function);
+  // Create a function or eval context.
+  Handle<Context> NewFunctionContext(int length, Handle<JSFunction> function,
+                                     ScopeType scope_type);
 
   // Create a catch context.
   Handle<Context> NewCatchContext(Handle<JSFunction> function,