Fix code search input for different views (#30678)

Now only show the "code search" on the repo home page, because it only
does global search.
So do not show it when viewing file or directory to avoid misleading
users (it doesn't search in a directory)

routers/web/repo/commit.go

@@ -212,8 +212,6 @@ func SearchCommits(ctx *context.Context) {
 
 // FileHistory show a file's reversions
 func FileHistory(ctx *context.Context) {
-	ctx.Data["IsRepoToolbarCommits"] = true
-
 	fileName := ctx.Repo.TreePath
 	if len(fileName) == 0 {
 		Commits(ctx)