title: Files on branch without being merged into it
body: <p>I am working on a project that has many different branches, one of which is called 'live' which has all of the code that is currently running on a live server. However recently some changes have managed to make their way onto this live branch, without being merged in, from a branch called 'test_theme'.</p>
  
  <p>I have looked through the history of the repository and at no point can I see anything that says that 'test_theme' has been merged into 'live'.</p>
  
  <p>How would one go around trying to find out how these changes managed to make it onto the 'live' branch with out being merged into it?</p>