Cast: Remove obsolete flavor dimension

PiperOrigin-RevId: 259582498

demos/cast/build.gradle

@@ -47,17 +47,6 @@ android {
         // The demo app isn't indexed and doesn't have translations.
         disable 'GoogleAppIndexingWarning','MissingTranslation'
     }
-
-    flavorDimensions "receiver"
-
-    productFlavors {
-        defaultCast {
-            dimension "receiver"
-            manifestPlaceholders =
-                    [castOptionsProvider: "com.google.android.exoplayer2.ext.cast.DefaultCastOptionsProvider"]
-        }
-    }
-
 }
 
 dependencies {

demos/cast/src/main/AndroidManifest.xml

@@ -25,7 +25,7 @@
       android:largeHeap="true" android:allowBackup="false">
 
     <meta-data android:name="com.google.android.gms.cast.framework.OPTIONS_PROVIDER_CLASS_NAME"
-        android:value="${castOptionsProvider}" />
+        android:value="com.google.android.exoplayer2.ext.cast.DefaultCastOptionsProvider"/>
 
     <activity android:name="com.google.android.exoplayer2.castdemo.MainActivity"
         android:configChanges="keyboard|keyboardHidden|orientation|screenSize|screenLayout|smallestScreenSize|uiMode"