Change BrowserBackupAgent path to absolute inside manifest

Change-Id: I54e990d9b829be54656a5904cb1427a2d2867999
diff --git a/AndroidManifest.xml.jinja2 b/AndroidManifest.xml.jinja2
index eecadf2..3499f52 100644
--- a/AndroidManifest.xml.jinja2
+++ b/AndroidManifest.xml.jinja2
@@ -53,7 +53,7 @@
     <application   android:name="com.android.browser.Browser"
                    android:label="{{ apk_label }}"
                    android:icon="@mipmap/ic_launcher_browser"
-                   android:backupAgent=".BrowserBackupAgent"
+                   android:backupAgent="com.android.browser.BrowserBackupAgent"
                    android:hardwareAccelerated="true"
                    android:taskAffinity="{{ apk_task_affinity }}"
                    android:theme="@style/BrowserBase" >