Meu app para de funcionar depois que tentei add Up Navigation

Meu app para quando eu uso Up navigation.
Eu fiz mudanças apenas em uma das activity e quando eu rodo o app,todas as outras activities funcionam exceto a ColorActivity. Eu fiz mudanças apenas nas duas partes abaixo para adicionar Up Navigation.
Alguém pode me ajudar?

AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>

<application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:supportsRtl="true"
    android:theme="@style/AppTheme">
    <activity android:name=".MainActivity">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <activity
        android:name=".NumbersActivity"
        android:label="@string/category_numbers"
        android:parentActivityName=".MainActivity">

        <!-- Parent activity meta-data to support 4.0 and lower -->
        <meta-data
            android:name="android.support.PARENT_ACTIVITY"
            android:value=".MainActivity"/>
    </activity>
    <activity
        android:name=".FamilyActivity"
        android:label="@string/category_family"
        android:parentActivityName=".MainActivity">

        <!-- Parent activity meta-data to support 4.0 and lower -->
        <meta-data
            android:name="android.support.PARENT_ACTIVITY"
            android:value=".MainActivity"/>
    </activity>
    <activity
        android:name=".ColorsActivity"
        android:label="@string/category_colors"
        android:parentActivityName=".MainActivity">

        <!-- Parent activity meta-data to support 4.0 and lower -->
        <meta-data
            android:name="android.support.PARENT_ACTIVITY"
            android:value=".MainActivity"/>
    </activity>
    <activity
        android:name=".PhrasesActivity"
        android:label="@string/category_phrases"
        android:parentActivityName=".MainActivity">

        <!-- Parent activity meta-data to support 4.0 and lower -->
        <meta-data
            android:name="android.support.PARENT_ACTIVITY"
            android:value=".MainActivity"/>
    </activity>
</application>

ColorActivity.java
/*

  • Copyright © 2016 The Android Open Source Project
  • Licensed under the Apache License, Version 2.0 (the “License”);
  • you may not use this file except in compliance with the License.
  • You may obtain a copy of the License at
  •  http://www.apache.org/licenses/LICENSE-2.0
    
  • Unless required by applicable law or agreed to in writing, software
  • distributed under the License is distributed on an “AS IS” BASIS,
  • WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  • See the License for the specific language governing permissions and
  • limitations under the License.
    */
    package com.example.android.miwok;

import android.content.Context;
import android.media.AudioManager;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.support.v4.app.NavUtils;
import android.support.v7.app.AppCompatActivity;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;

import java.util.ArrayList;

public class ColorsActivity extends AppCompatActivity {

/** Handles playback of all the sound files */
private MediaPlayer mMediaPlayer;

/** Handles audio focus when playing a sound file */
private AudioManager mAudioManager;

/**
 * This listener gets triggered when the {@link MediaPlayer} has completed
 * playing the audio file.
 * Em vez de criar um "onCompletionListener" sempre que clicar num item da lista
 * criamos um único "onCompletionListener" que poderá ser utilizado quando necessario.
 */
private MediaPlayer.OnCompletionListener mCompletionListener = new MediaPlayer.OnCompletionListener() {
    @Override
    public void onCompletion(MediaPlayer mediaPlayer) {
        // Now that the sound file has finished playing, release the media player resources.
        releaseMediaPlayer();
    }
};

/**
 * This listener gets triggered whenever the audio focus changes
 * (i.e., we gain or lose audio focus because of another app or device).
 */
private AudioManager.OnAudioFocusChangeListener mOnAudioFocusChangeListener = new AudioManager.OnAudioFocusChangeListener() {
    @Override
    public void onAudioFocusChange(int focusChange) {
        if (focusChange == AudioManager.AUDIOFOCUS_LOSS_TRANSIENT ||
                focusChange == AudioManager.AUDIOFOCUS_LOSS_TRANSIENT_CAN_DUCK) {
            // The AUDIOFOCUS_LOSS_TRANSIENT case means that we've lost audio focus for a
            // short amount of time. The AUDIOFOCUS_LOSS_TRANSIENT_CAN_DUCK case means that
            // our app is allowed to continue playing sound but at a lower volume. We'll treat
            // both cases the same way because our app is playing short sound files.

            // Pause playback and reset player to the start of the file. That way, we can
            // play the word from the beginning when we resume playback.
            mMediaPlayer.pause();
            mMediaPlayer.seekTo(0);
        } else if (focusChange == AudioManager.AUDIOFOCUS_GAIN) {
            // The AUDIOFOCUS_GAIN case means we have regained focus and can resume playback.
            mMediaPlayer.start();
        } else if (focusChange == AudioManager.AUDIOFOCUS_LOSS) {
            // The AUDIOFOCUS_LOSS case means we've lost audio focus and
            // Stop playback and clean up resources
            releaseMediaPlayer();
        }
    }
};

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.word_list);
    getActionBar().setDisplayHomeAsUpEnabled(true);

    // Create and setup the {@link AudioManager} to request audio focus
    mAudioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);

    // Create a list of words
    final ArrayList<Word> words = new ArrayList<Word>();
    words.add(new Word("red", "weṭeṭṭi", R.drawable.color_red, R.raw.color_red));
    words.add(new Word("mustard yellow", "chiwiiṭә", R.drawable.color_mustard_yellow,
            R.raw.color_mustard_yellow));
    words.add(new Word("dusty yellow", "ṭopiisә", R.drawable.color_dusty_yellow,
            R.raw.color_dusty_yellow));
    words.add(new Word("green", "chokokki", R.drawable.color_green, R.raw.color_green));
    words.add(new Word("brown", "ṭakaakki", R.drawable.color_brown, R.raw.color_brown));
    words.add(new Word("gray", "ṭopoppi", R.drawable.color_gray, R.raw.color_gray));
    words.add(new Word("black", "kululli", R.drawable.color_black, R.raw.color_black));
    words.add(new Word("white", "kelelli", R.drawable.color_white, R.raw.color_white));

    // Create an {@link WordAdapter}, whose data source is a list of {@link Word}s. The
    // adapter knows how to create list items for each item in the list.
    WordAdapter adapter = new WordAdapter(this, words, R.color.category_colors);

    // Find the {@link ListView} object in the view hierarchy of the {@link Activity}.
    // There should be a {@link ListView} with the view ID called list, which is declared in the
    // word_list.xml layout file.
    ListView listView = (ListView) findViewById(R.id.list);

    // Make the {@link ListView} use the {@link WordAdapter} we created above, so that the
    // {@link ListView} will display list items for each {@link Word} in the list.
    listView.setAdapter(adapter);

    // Set a click listener to play the audio when the list item is clicked on
    listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> adapterView, View view, int position, long l) {
            // Release the media player if it currently exists because we are about to
            // play a different sound file
            releaseMediaPlayer();

            // Get the {@link Word} object at the given position the user clicked on
            Word word = words.get(position);

            // Request audio focus so in order to play the audio file. The app needs to play a
            // short audio file, so we will request audio focus with a short amount of time
            // with AUDIOFOCUS_GAIN_TRANSIENT.
            int result = mAudioManager.requestAudioFocus(mOnAudioFocusChangeListener,
                    AudioManager.STREAM_MUSIC, AudioManager.AUDIOFOCUS_GAIN_TRANSIENT);

            if (result == AudioManager.AUDIOFOCUS_REQUEST_GRANTED) {
                // We have audio focus now.

                // Create and setup the {@link MediaPlayer} for the audio resource associated
                // with the current word
                mMediaPlayer = MediaPlayer.create(ColorsActivity.this, word.getAudioResourceId());

                // Start the audio file
                mMediaPlayer.start();

                // Setup a listener on the media player, so that we can stop and release the
                // media player once the sound has finished playing.
                mMediaPlayer.setOnCompletionListener(mCompletionListener);
            }
        }
    });
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {
        // Id correspondente ao botão Up/Home da actionbar
        case android.R.id.home:
            NavUtils.navigateUpFromSameTask(this);
            return true;
    }
    return super.onOptionsItemSelected(item);
}

@Override
protected void onStop() {
    super.onStop();
    // When the activity is stopped, release the media player resources because we won't
    // be playing any more sounds.
    releaseMediaPlayer();
}

/**
 * Clean up the media player by releasing its resources.
 */
private void releaseMediaPlayer() {
    // If the media player is not null, then it may be currently playing a sound.
    if (mMediaPlayer != null) {
        // Regardless of the current state of the media player, release its resources
        // because we no longer need it.
        mMediaPlayer.release();

        // Set the media player back to null. For our code, we've decided that
        // setting the media player to null is an easy way to tell that the media player
        // is not configured to play an audio file at the moment.
        mMediaPlayer = null;

        // Regardless of whether or not we were granted audio focus, abandon it. This also
        // unregisters the AudioFocusChangeListener so we don't get anymore callbacks.
        mAudioManager.abandonAudioFocus(mOnAudioFocusChangeListener);
    }
}

}

ERRO
02-09 16:31:11.608 15853-15853/com.example.android.miwok E/AndroidRuntime: FATAL EXCEPTION: main
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.android.miwok/com.example.android.miwok.ColorsActivity}: java.lang.NullPointerException
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2308)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2362)
at android.app.ActivityThread.access$700(ActivityThread.java:168)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1329)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:176)
at android.app.ActivityThread.main(ActivityThread.java:5493)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1225)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1041)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.NullPointerException
at com.example.android.miwok.ColorsActivity.onCreate(ColorsActivity.java:86)
at android.app.Activity.performCreate(Activity.java:5372)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1104)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2270)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2362)
at android.app.ActivityThread.access$700(ActivityThread.java:168)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1329)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:176)
at android.app.ActivityThread.main(ActivityThread.java:5493)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1225)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1041)
at dalvik.system.NativeStart.main(Native Method)

Resolvido