Add setting to control tabs per app behavior

    Bug: 5890701

Change-Id: I6a47c7bff260dd8ded3a4c360f186ce8f670c67e
diff --git a/src/com/android/browser/PreferenceKeys.java b/src/com/android/browser/PreferenceKeys.java
index ff42aaf..1828032 100644
--- a/src/com/android/browser/PreferenceKeys.java
+++ b/src/com/android/browser/PreferenceKeys.java
@@ -46,6 +46,7 @@
     static final String PREF_RESET_DEFAULT_PREFERENCES = "reset_default_preferences";
     static final String PREF_SEARCH_ENGINE = "search_engine";
     static final String PREF_WEBSITE_SETTINGS = "website_settings";
+    static final String PREF_ALLOW_APP_TABS = "allow_apptabs";
 
     // ----------------------
     // Keys for debug_preferences.xml