title: How to set app_name based on built type and build flavor using gradle
body: <p>I have my <code>bluid.gradle</code> set different app_names for debug and release like this:</p>
  
  <pre><code>buildTypes {
      debug {
          ...
          resValue "string", "app_name", "App Dev"
      }
  
      release {
          ...
          resValue "string", "app_name", "App"
      }
  }
  </code></pre>
  
  <p>Now, I want to add two flavors for two different targets of the app: </p>
  
  <pre><code>buildTypes {
      debug {
          ...
          resValue "string", "app_name", "App Dev"
      }
  
      release {
          ...
          resValue "string", "app_name", "App"
      }
  }
  
  productFlavors {
      app {
          ...
          resValue "string", "app_name", "App"
      }
      client {
          ...
          resValue "string", "app_name", "Client App"
      }
  }
  </code></pre>
  
  <p>The question is, how can I set the app_name to match this output:</p>
  
  <ul>
  <li>appDebug -> "App Dev" </li>
  <li>appRelease -> "App" </li>
  <li>clientDebug -> "Client App Dev" </li>
  <li>clientRelease-> "Client App"</li>
  </ul>
  
  <p>I have seen some answers using resources, but I want to know if there is a way to do so just using gradle.</p>