Integrate Save WebArchive with download manager.

Bug:2968359
Bug:2905874

Change-Id: I80f557af415b03698325397d7a10d66bb0c10827
diff --git a/res/menu/browser.xml b/res/menu/browser.xml
index beaa8f3..7a59ffd 100644
--- a/res/menu/browser.xml
+++ b/res/menu/browser.xml
@@ -57,6 +57,8 @@
             android:title="@string/menu_preferences"
             android:icon="@drawable/ic_settings_holo_dark"
             android:alphabeticShortcut="p" />
+        <item android:id="@+id/save_webarchive_menu_id"
+            android:title="@string/menu_save_webarchive" />
         <!-- followings are debug only -->
         <item android:id="@+id/dump_nav_menu_id"
             android:title="@string/dump_nav"