Blimp OAuth2 token retreival on application start up.

blimp/client/core/android/java/src/org/chromium/blimp/core/settings/AboutBlimpPreferences.java

Index: blimp/client/core/android/java/src/org/chromium/blimp/core/settings/AboutBlimpPreferences.java
diff --git a/blimp/client/core/android/java/src/org/chromium/blimp/core/settings/AboutBlimpPreferences.java b/blimp/client/core/android/java/src/org/chromium/blimp/core/settings/AboutBlimpPreferences.java
index c03d0829f50d32d15bfe36edec2d2e18e3c75ae1..74dc0325dc744a0cbcc44843ce2fc221f74e1b48 100644
--- a/blimp/client/core/android/java/src/org/chromium/blimp/core/settings/AboutBlimpPreferences.java
+++ b/blimp/client/core/android/java/src/org/chromium/blimp/core/settings/AboutBlimpPreferences.java
@@ -16,6 +16,7 @@ import android.support.v7.app.AlertDialog;
 
 import org.chromium.base.VisibleForTesting;
 import org.chromium.blimp.R;
+import org.chromium.blimp.core.common.PreferencesUtil;
 import org.chromium.blimp_public.BlimpSettingsCallbacks;
 
 /**
@@ -23,15 +24,6 @@ import org.chromium.blimp_public.BlimpSettingsCallbacks;
  */
 public class AboutBlimpPreferences extends PreferenceFragment {
 
-    /**
-     * Blimp switch preference key, also the key for this PreferenceFragment.
-     */
-    public static final String PREF_BLIMP_SWITCH = "blimp_switch";
-    /**
-     * Blimp assigner URL preference key.
-     */
-    public static final String PREF_ASSIGNER_URL = "blimp_assigner_url";
-
     private static BlimpSettingsCallbacks sSettingsCallback;
 
     /**
@@ -44,7 +36,7 @@ public class AboutBlimpPreferences extends PreferenceFragment {
         Preference blimpSetting = new Preference(fragment.getActivity());
         blimpSetting.setTitle(R.string.blimp_about_blimp_preferences);
         blimpSetting.setFragment(AboutBlimpPreferences.class.getName());
-        blimpSetting.setKey(AboutBlimpPreferences.PREF_BLIMP_SWITCH);
+        blimpSetting.setKey(PreferencesUtil.PREF_BLIMP_SWITCH);
 
         screen.addPreference(blimpSetting);
         fragment.setPreferenceScreen(screen);
@@ -74,7 +66,7 @@ public class AboutBlimpPreferences extends PreferenceFragment {
     private void setupBlimpSwitch() {
         // TODO(xingliu): Use {@link ChromeSwitchPreference} after move this class to Chrome.
         // http://crbug.com/630675
-        final Preference pref = findPreference(PREF_BLIMP_SWITCH);
+        final Preference pref = findPreference(PreferencesUtil.PREF_BLIMP_SWITCH);
 
         pref.setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() {
             @Override
@@ -98,7 +90,8 @@ public class AboutBlimpPreferences extends PreferenceFragment {
     private void setupAssignerPreferences() {
         final Activity activity = getActivity();
 
-        final ListPreference listPreference = (ListPreference) findPreference(PREF_ASSIGNER_URL);
+        final ListPreference listPreference = (ListPreference) findPreference(
+                PreferencesUtil.PREF_ASSIGNER_URL);
         listPreference.setSummary(listPreference.getValue());
 
         listPreference.setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() {