title: BuildConfig.VERSION_CODE is missing after update to 'com.android.tools.build:gradle:4.1.0'
body: <p>I have a multi modular app and for some reason VERSION_CODE generated field has disappeared from all modules except the root one, I have tested it on one more project and it behaves the same. Right now I have simply downgraded to 4.0.1, but thats just a workaround.</p>
  <p>I need to restore BuildConfig.VERSION_CODE in all modules using gradle tools 4.1.0</p>
  <p>Would appreciate any help.</p>
  <p>defaultConfig example:</p>
  <pre><code>buildFeatures {
      buildConfig = true
  }
  
  defaultConfig {
      minSdkVersion global[&quot;androidMinSdkVersion&quot;]
      targetSdkVersion global[&quot;androidTargetSdkVersion&quot;]
  
      versionCode global[&quot;versionString&quot;]
  
      javaCompileOptions {
          annotationProcessorOptions {
              includeCompileClasspath true
          }
      }
  }
  </code></pre>
  <p>Here comes the BuildConfig code on 4.0.1</p>
  <pre><code>public final class BuildConfig {
    public static final boolean DEBUG = Boolean.parseBoolean(&quot;true&quot;);
    public static final String APPLICATION_ID = &quot;app&quot;;
    public static final String BUILD_TYPE = &quot;debug&quot;;
    public static final String FLAVOR = &quot;flavour&quot;;
    public static final int VERSION_CODE = 107;
    public static final String VERSION_NAME = &quot;6.0.0&quot;;
    // Field from build type: debug
    public static final String AMQP_URL = &quot;url&quot;;
    // Field from build type: debug
    public static final String API_VERSION_SUFFIX = &quot;V_04_04_09&quot;;
    // Field from build type: debug
    public static final String BASE_URL = &quot;url&quot;;
    // Field from product flavor: flavour
    public static final String BUILD_FLAVOR = &quot;flavour&quot;;
    // Field from build type: debug
    public static final int DB_VERSION = 53;
  }
  </code></pre>
  <p>And here is 4.1.0</p>
  <pre><code>public final class BuildConfig {
    public static final boolean DEBUG = Boolean.parseBoolean(&quot;true&quot;);
    public static final String APPLICATION_ID = &quot;app&quot;;
    public static final String BUILD_TYPE = &quot;debug&quot;;
    public static final String FLAVOR = &quot;flavour&quot;;
    public static final String VERSION_NAME = &quot;6.0.0&quot;;
    // Field from build type: debug
    public static final String AMQP_URL = &quot;url&quot;;
    // Field from build type: debug
    public static final String API_VERSION_SUFFIX = &quot;V_04_04_09&quot;;
    // Field from build type: debug
    public static final String BASE_URL = &quot;url&quot;;
    // Field from product flavor: flavour
    public static final String BUILD_FLAVOR = &quot;flavour&quot;;
    // Field from build type: debug
    public static final int DB_VERSION = 53;
  }
  </code></pre>