am 831ca9d3: Document best practices for display intent activities.

         *         .build();</pre>

         *

         * <p>The activity to launch needs to allow embedding, must be exported, and

         * should have an empty task affinity.

         * should have an empty task affinity. It is also recommended to use the device

         * default light theme.

         *

         * <p>Example AndroidManifest.xml entry:

         * <pre class="prettyprint">

         * <activity android:name="com.example.MyDisplayActivity"

         *     android:exported="true"

         *     android:allowEmbedded="true"

         *     android:taskAffinity=&quot;&quot; /&gt;</pre>

         *     android:taskAffinity=""

         *     android:theme=&quot;@android:style/Theme.DeviceDefault.Light&quot; /&gt;</pre>

         *

         * @param intent the {@link PendingIntent} for an activity

         * @return this object for method chaining