Use constants in place of strings, and remove unused code.

Change-Id: I4d27cf74edefcabacffbfc59fa8fe28f5b592fa7
diff --git a/src/com/android/browser/BrowserBookmarksPage.java b/src/com/android/browser/BrowserBookmarksPage.java
index 522d37e..4a3ae1f 100644
--- a/src/com/android/browser/BrowserBookmarksPage.java
+++ b/src/com/android/browser/BrowserBookmarksPage.java
@@ -354,8 +354,8 @@
         super.onCreate(icicle);
 
         Bundle args = getArguments();
-        mCreateShortcut = args == null ? false : args.getBoolean("create_shortcut", false);
-        mDisableNewWindow = args == null ? false : args.getBoolean("disable_new_window", false);
+        mCreateShortcut = args == null ? false : args.getBoolean(EXTRA_SHORTCUT, false);
+        mDisableNewWindow = args == null ? false : args.getBoolean(EXTRA_DISABLE_WINDOW, false);
     }
 
     @Override
@@ -520,8 +520,8 @@
                     if (data != null && (extras = data.getExtras()) != null) {
                         // If there are extras, then we need to save
                         // the edited bookmark. This is done in updateRow()
-                        String title = extras.getString("title");
-                        String url = extras.getString("url");
+                        String title = extras.getString(BrowserContract.Bookmarks.TITLE);
+                        String url = extras.getString(BrowserContract.Bookmarks.URL);
                         if (title != null && url != null) {
                             updateRow(extras);
                         }
@@ -562,7 +562,7 @@
             values.put(BrowserContract.Bookmarks.URL, url);
         }
 
-        if (map.getBoolean("invalidateThumbnail") == true) {
+        if (map.getBoolean(AddBookmarkPage.REMOVE_THUMBNAIL)) {
             values.putNull(BrowserContract.Bookmarks.THUMBNAIL);
         }