Adding everything to the AndroidManifest for the SyncAdapter

AndroidManifest_1_authentication.xml

        <!-- SyncAdapter's dummy authentication service -->
        <service
            android:name=".sync.SunshineAuthenticatorService"
            >
            <intent-filter>
                <action android:name="android.accounts.AccountAuthenticator" />
            </intent-filter>
            <meta-data
                android:name="android.accounts.AccountAuthenticator"
                android:resource="@xml/authenticator" />
        </service>

AndroidManifest_2_provider.xml

        <provider
            android:authorities="@string/content_authority"
            android:name=".data.WeatherProvider"
            android:exported="false"
            android:syncable="true" />

AndroidManifest_3_permissions.xml

    <!-- Permissions required by the sync adapter -->
    <uses-permission
        android:name="android.permission.READ_SYNC_SETTINGS"/>
    <uses-permission
        android:name="android.permission.WRITE_SYNC_SETTINGS"/>
    <uses-permission
        android:name="android.permission.AUTHENTICATE_ACCOUNTS"/>

AndroidManifest_4_syncadapter.xml

        <!-- The SyncAdapter service -->
        <service
            android:name=".sync.SunshineSyncService"
            android:exported="true"
            >
            <intent-filter>
                <action android:name="android.content.SyncAdapter" />
            </intent-filter>
            <meta-data
                android:name="android.content.SyncAdapter"
                android:resource="@xml/syncadapter" />
        </service>