Reland of [api] Restrict Template::Set to take templates or primitive values

include/v8.h

Index: include/v8.h
diff --git a/include/v8.h b/include/v8.h
index db2178b73becb2c7ad76a5f28e8b81e4c14d1c33..b01a8cc54fe4e452bedd64832e95554c7c658429 100644
--- a/include/v8.h
+++ b/include/v8.h
@@ -4102,7 +4102,11 @@
  */
 class V8_EXPORT Template : public Data {
  public:
-  /** Adds a property to each instance created by this template.*/
+  /**
+   * Adds a property to each instance created by this template.
+   *
+   * The property must be defined either as a primitive value, or a template.
+   */
   void Set(Local<Name> name, Local<Data> value,
            PropertyAttribute attributes = None);
   V8_INLINE void Set(Isolate* isolate, const char* name, Local<Data> value);