Preloading support in browser

	   Apps like the QSB can request the browser to preload a
	   web page.
           - preloaded pages are not added to the browser history
	     if they'r not seen by the user
	   - when a request is received, a new tab is created for the
	     preloaded page, but not added to the tab list
 	   - upon receiving the view intent for the preloaded page
             the tab is added to the tab list, and shown
	   - if several pages are preloaded consecutively in the same tab,
             the back stack is cleared before it is displayed
           - preloaded pages use the main browser cookie jar, so pages that
             have never been viewed by the user can drop cookies

Change-Id: I9ed21f2c9560fda0ed042b460b73bb33988a2e8a
diff --git a/src/com/android/browser/PreferenceKeys.java b/src/com/android/browser/PreferenceKeys.java
index bc8d38f..144d505 100644
--- a/src/com/android/browser/PreferenceKeys.java
+++ b/src/com/android/browser/PreferenceKeys.java
@@ -94,4 +94,9 @@
     static final String PREF_SAVE_FORMDATA = "save_formdata";
     static final String PREF_SHOW_SECURITY_WARNINGS = "show_security_warnings";
 
+    // ----------------------
+    // Keys for bandwidth_preferences.xml
+    // ----------------------
+    static final String PREF_DATA_PRELOAD = "preload_enabled";
+
 }