Explicitly export content providers

In a future version of Android, the default value for
<provider android:exported> will change from true to false.
Explicitly set android:exported="true"

Bug: 3306452
Change-Id: I3e75e2ee53d42b2aaad601bcff8f6b27bbe3d58f
diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index f2aeac9..4370a42 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -33,6 +33,7 @@
             android:authorities="contacts;com.android.contacts"
             android:label="@string/provider_label"
             android:multiprocess="false"
+            android:exported="true"
             android:readPermission="android.permission.READ_CONTACTS"
             android:writePermission="android.permission.WRITE_CONTACTS">
             <path-permission
@@ -50,6 +51,7 @@
         <provider android:name="CallLogProvider"
             android:authorities="call_log"
             android:syncable="false" android:multiprocess="false"
+            android:exported="true"
             android:readPermission="android.permission.READ_CALL_LOG"
             android:writePermission="android.permission.WRITE_CALL_LOG">
         </provider>
@@ -57,6 +59,7 @@
         <provider android:name="VoicemailContentProvider"
             android:authorities="com.android.voicemail"
             android:syncable="false" android:multiprocess="false"
+            android:exported="true"
             android:permission="com.android.voicemail.permission.ADD_VOICEMAIL">
         </provider>