@tree_edit_project is no longer used

Feedback:
https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/7237#note_21626434

app/controllers/concerns/creates_commit.rb

@@ -101,7 +101,6 @@ module CreatesCommit
   def set_commit_variables
     if can?(current_user, :push_code, @project)
       # Edit file in this project
-      @tree_edit_project = @project
       @mr_source_project = @project
       if @project.forked?
@@ -114,10 +113,8 @@ module CreatesCommit
         @mr_target_branch = @ref || @target_branch
       end
     else
-      # Edit file in fork
-      @tree_edit_project = current_user.fork_of(@project)
       # Merge request from fork to this project
-      @mr_source_project = @tree_edit_project
+      @mr_source_project = current_user.fork_of(@project)
       @mr_target_project = @project
       @mr_target_branch = @ref || @target_branch
     end