title: Unknown provider for $httpParamSerializer
body: <p>I came across an Angular.js service named <a href="https://docs.angularjs.org/api/ng/service/$httpParamSerializer" rel="nofollow"><code>$httpParamSerializer</code></a> and thought it could be useful for my code. However, when I tried to inject it Angular.js didn't recognize it and threw an "unknown provider" error.</p>
  
  <p>Isn't <code>$httpParamSerializer</code> a built-in service (just like <code>$http</code>)? Why is this happening?</p>
  
  <p>I have no problem injecting other built-in services such as <code>$http</code>, <code>$httpBackend</code> etc.</p>
  
  <p>Thanks.</p>