internal/lsp/cache: invalidate metadata even without Create

When a new file is opened, the first time we learn about it will be a
didOpen event. We need to invalidate the package's metadata in that
case too.

Fixes #35638.

Change-Id: I36c6171e9c959c48ede9e125679e8dd1be7609f4
Reviewed-on: https://go-review.googlesource.com/c/tools/+/210559
Reviewed-by: Rebecca Stambler <[email protected]>

Author: heschi

internal/lsp/cache/snapshot.go

@@ -565,7 +565,7 @@ func (v *view) invalidateContent(ctx context.Context, f source.File, kind source
 	// Make a rough estimate of what metadata to invalidate by finding the package IDs
 	// of all of the files in the same directory as this one.
 	// TODO(rstambler): Speed this up by mapping directories to filenames.
-	if action == source.Create {
+	if originalFH == nil {
 		if dirStat, err := os.Stat(dir(f.URI().Filename())); err == nil {
 			for _, uri := range v.snapshot.getFileURIs() {
 				if fdirStat, err := os.Stat(dir(uri.Filename())); err == nil {