Disable all filegroups in mixed builds

Rather than individually denylisting filegroups until we prioritize a
solution for mixed builds that will correctly integrate into uses such
as proto, aidl, gensrcs, etc.

Test: mixed_droid
Change-Id: Iddbd391af7dd7cabc892b2b26dbc68e3aa506471
diff --git a/android/filegroup.go b/android/filegroup.go
index 6b11172..af4d89a 100644
--- a/android/filegroup.go
+++ b/android/filegroup.go
@@ -234,7 +234,8 @@
 }
 
 func (fg *fileGroup) IsMixedBuildSupported(ctx BaseModuleContext) bool {
-	return true
+	// TODO(b/247782695), TODO(b/242847534) Fix mixed builds for filegroups
+	return false
 }
 
 func (fg *fileGroup) ProcessBazelQueryResponse(ctx ModuleContext) {