Fix typos

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=180778084

extensions/ima/src/main/java/com/google/android/exoplayer2/ext/ima/ImaAdsLoader.java

@@ -332,7 +332,7 @@ public final class ImaAdsLoader extends Player.DefaultEventListener implements A
    *
    * <p>Ads will be requested automatically when the player is prepared if this method has not been
    * called, so it is only necessary to call this method if you want to request ads before preparing
-   * the player
+   * the player.
    *
    * @param adUiViewGroup A {@link ViewGroup} on top of the player that will show any ad UI.
    */

library/dash/src/main/java/com/google/android/exoplayer2/source/dash/DashMediaPeriod.java

@@ -104,7 +104,7 @@ import java.util.Map;
 
   /**
    * Updates the {@link DashManifest} and the index of this period in the manifest.
-   * <p>
+   *
    * @param manifest The updated manifest.
    * @param periodIndex the new index of this period in the updated manifest.
    */