Fix common typo "the the" and javadoc in media2

The main purpose of this CL is to fix "the the" typo. While fixing them,
it is discovered that javadoc of skipToPlaylistItem of SessionPlayer and
MediaController are incorrect so this CL fixes them as well.

Test: ./gradlew tipOfTreeDocs
Change-Id: I7a352b663efe5eb5316f41ec7c43b8b937428cc4

diff --git a/media2/common/src/main/java/androidx/media2/common/SessionPlayer.java b/media2/common/src/main/java/androidx/media2/common/SessionPlayer.java
index b8207ac..2d1b17f 100644
--- a/media2/common/src/main/java/androidx/media2/common/SessionPlayer.java
+++ b/media2/common/src/main/java/androidx/media2/common/SessionPlayer.java

@@ -681,7 +681,7 @@
     public abstract ListenableFuture<PlayerResult> skipToNextPlaylistItem();
 
     /**
-     * Skips to the the media item.
+     * Skips to the item in the playlist at the index.
      * <p>
      * The implementation must notify registered callbacks with
      * {@link PlayerCallback#onCurrentMediaItemChanged(SessionPlayer, MediaItem)} when it's

diff --git a/media2/integration-tests/testapp/src/main/java/androidx/media2/integration/testapp/VideoSelectorActivity.java b/media2/integration-tests/testapp/src/main/java/androidx/media2/integration/testapp/VideoSelectorActivity.java
index 123b7a0..36a69f1 100644
--- a/media2/integration-tests/testapp/src/main/java/androidx/media2/integration/testapp/VideoSelectorActivity.java
+++ b/media2/integration-tests/testapp/src/main/java/androidx/media2/integration/testapp/VideoSelectorActivity.java

@@ -290,12 +290,12 @@
             }
         }
 
-        // now add the the sorted directories to the result set.
+        // now add the sorted directories to the result set.
         for (VideoItem vi : dirs.values()) {
             retVal.add(vi);
         }
 
-        // finally add the the sorted files to the result set.
+        // finally add the sorted files to the result set.
         for (VideoItem vi : files.values()) {
             retVal.add(vi);
         }

diff --git a/media2/session/src/main/java/androidx/media2/session/MediaController.java b/media2/session/src/main/java/androidx/media2/session/MediaController.java
index 2624d9c..35c93f1 100644
--- a/media2/session/src/main/java/androidx/media2/session/MediaController.java
+++ b/media2/session/src/main/java/androidx/media2/session/MediaController.java

@@ -1034,7 +1034,7 @@
      * <p>
      * This calls {@link SessionPlayer#skipToPlaylistItem(int)}.
      *
-     * @param index The item in the playlist you want to play
+     * @param index The index of the item you want to play in the playlist
      */
     @NonNull
     public ListenableFuture<SessionResult> skipToPlaylistItem(@IntRange(from = 0) int index) {
@@ -1968,7 +1968,7 @@
     }
 
     /**
-     * Holds information about the the way volume is handled for this session.
+     * Holds information about the way volume is handled for this session.
      */
     // The same as MediaController.PlaybackInfo
     @VersionedParcelize

diff --git a/media2/session/src/main/java/androidx/media2/session/MediaSession.java b/media2/session/src/main/java/androidx/media2/session/MediaSession.java
index c6f997e..a1c663e 100644
--- a/media2/session/src/main/java/androidx/media2/session/MediaSession.java
+++ b/media2/session/src/main/java/androidx/media2/session/MediaSession.java

@@ -95,7 +95,7 @@
  * session.
  * <p>
  * When a session receive transport control commands, the session sends the commands directly to
- * the the underlying media player set by {@link Builder} or {@link #updatePlayer}.
+ * the underlying media player set by {@link Builder} or {@link #updatePlayer}.
  * <p>
  * When an app is finished performing playback it must call {@link #close()} to clean up the session
  * and notify any controllers. The app is responsible for closing the underlying player after