Support naked files.

Implements https://github.com/wixtoolset/issues/issues/7696.

`File` elements can appear where `Component` elements do in WiX v4. The
compiler generates an appropriate per-file component. Naked files under
`Directory`, `DirectoryRef`, `Fragment`, `StandardDirectory`, or
`Package` elements are included in a package via the [default-feature
feature](https://github.com/wixtoolset/issues/issues/7581). Naked files
appearing under `ComponentGroup`, `Feature`, `FeatureRef`, and
`FeatureGroup` generate the component and the reference to the parent
element.

Components and naked Files default to being installed to INSTALLFOLDER
(including a default INSTALLFOLDER if one isn't otherwise authored).

1 files changed, 5 insertions, 0 deletions

diff --git a/src/api/wix/WixToolset.Data/ErrorMessages.cs b/src/api/wix/WixToolset.Data/ErrorMessages.cs
index e7c88613..79b835cd 100644
--- a/src/api/wix/WixToolset.Data/ErrorMessages.cs
+++ b/src/api/wix/WixToolset.Data/ErrorMessages.cs
@@ -2256,6 +2256,11 @@ namespace WixToolset.Data
             return Message(sourceLineNumbers, Ids.IllegalInnerText, "The {0} element contains inner text which is obsolete. Use the {1} attribute instead.", elementName, attributeName);
         }
 
+        public static Message IllegalAttributeWhenNested(SourceLineNumber sourceLineNumbers, string attributeName)
+        {
+            return Message(sourceLineNumbers, Ids.IllegalAttributeWhenNested, "The File element contains an attribute '{0}' that cannot be used in a File element that is a child of a Component element.", attributeName);
+        }
+
         private static Message Message(SourceLineNumber sourceLineNumber, Ids id, string format, params object[] args)
         {
             return new Message(sourceLineNumber, MessageLevel.Error, (int)id, format, args);