Merge branch '40273_404_on_commits_page_when_all_files_on_branch_deleted' into 'master'

Fix 404 on commits list for branch that doesn't have any files

See merge request gitlab-org/gitlab-ce!15603

app/controllers/projects/commits_controller.rb

@@ -45,8 +45,7 @@ class Projects::CommitsController < Projects::ApplicationController
   private
 
   def set_commits
-    render_404 unless request.format == :atom || @repository.blob_at(@commit.id, @path) || @repository.tree(@commit.id, @path).entries.present?
-
+    render_404 unless @path.empty? || request.format == :atom || @repository.blob_at(@commit.id, @path) || @repository.tree(@commit.id, @path).entries.present?
     @limit, @offset = (params[:limit] || 40).to_i, (params[:offset] || 0).to_i
     search = params[:search]