title: Build type specific folder not recognized for a product flavor
body: <p>I have configured my project to have multiple product flavors. I have the following code in my module <code>build.gradle</code>:</p>
  
  <pre><code>android {
      // Rest of the configuration omitted for clarity
      buildTypes {
          debug {
              // ...
          }
  
          release {
              // ...
          }
      }
  
      productFlavors {
          paid
          free
      }
  }
  </code></pre>
  
  <p>If I create a file (any file: Java, resources, ...), in the <code>paid</code>, <code>free</code>, <code>debug</code> or <code>release</code>, it is recognized by Android Studio and I can use it in my project.</p>
  
  <p>However, if the same file is created in <code>paidDebug</code> (or a similar folder) it is not recognized in Android Studio. Do I need any extra configuration for this to work? Is this not supported (yet)?</p>