Merge "docs: Updating Direct Boot N preview docs for DP2" into mnc-mr-docs am: 69f6e5b0

can run during Direct Boot mode or access device encrypted

storage. Apps register with the system by marking components as

<i>encryption aware</i>. To mark your component as encryption aware, set the

<code>android:encryptionAware</code> attribute to true in your manifest.<p>

<code>android:directBootAware</code> attribute to true in your manifest.<p>

<p>Encryption aware components can register to receive a

<code>LOCKED_BOOT_COMPLETED</code> broadcast message from the

<pre>

<receiever

  android:encryptionAware="true" >

  android:directBootAware="true" >

  ...

  <intent-filter>

    <action android:name="android.intent.action.LOCKED_BOOT_COMPLETED" />

<p>To access device encrypted storage, create a second

{@link android.content.Context} instance by calling

<code>Context.createDeviceEncryptedStorageContext()</code>. All storage API

<code>Context.createDeviceProtectedStorageContext()</code>. All storage API

calls made using this context access the device encrypted storage. The

following example accesses the device encrypted storage and opens an existing

app data file:</p>

<pre>

Context directBootContext = Context.createDeviceEncryptedStorageContext();

Context directBootContext = appContext.createDeviceProtectedStorageContext();

// Access appDataFilename that lives in device encrypted storage

FileInputStream inStream = directBootContext.openFileInput(appDataFilename);

// Use inStream to read content...

<p>If a user updates their device to use Direct Boot mode, you might have

existing data that needs to get migrated to device encrypted storage. Use

<code>Context.migrateSharedPreferencesFrom()</code> and

<code>Context.migrateDatabaseFrom()</code> to migrate preference and database

<code>Context.moveSharedPreferencesFrom()</code> and

<code>Context.moveDatabaseFrom()</code> to migrate preference and database

data between credential encrypted storage and device encrypted storage.</p>

<p>Use your best judgment when deciding what data to migrate from credential