[Android Refactor] Reland: Merge WebappDataStorage#LAST_USED_UNSET and LAST_USED_INVALID

chrome/android/junit/src/org/chromium/chrome/browser/webapps/WebappDataStorageTest.java

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package org.chromium.chrome.browser.webapps;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
 
 import android.content.Context;
 import android.content.Intent;
 import android.content.SharedPreferences;
 import android.graphics.Bitmap;
 import android.os.AsyncTask;
 
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
-
 import org.robolectric.RuntimeEnvironment;
 import org.robolectric.annotation.Config;
 import org.robolectric.shadows.ShadowLooper;
 
 import org.chromium.base.ContextUtils;
 import org.chromium.base.test.util.Feature;
 import org.chromium.blink_public.platform.WebDisplayMode;
 import org.chromium.chrome.browser.ShortcutHelper;
 import org.chromium.chrome.browser.webapps.WebappDataStorage.Clock;
 import org.chromium.testing.local.BackgroundShadowAsyncTask;
@@ skipping 155 matching lines @@
         WebappDataStorage.setClockForTests(clock);
 
         // Opening a data storage doesn't count as a launch.
         WebappDataStorage storage = WebappDataStorage.open("test");
         assertTrue(!storage.wasLaunchedRecently());
 
         // When the last used time is updated, then it is a launch.
         storage.updateLastUsedTime();
         assertTrue(storage.wasLaunchedRecently());
 
-        long lastUsedTime = mSharedPreferences.getLong(WebappDataStorage.KEY_LAST_USED,
-                WebappDataStorage.LAST_USED_INVALID);
+        long lastUsedTime = mSharedPreferences.getLong(
+                WebappDataStorage.KEY_LAST_USED, WebappDataStorage.TIMESTAMP_INVALID);
 
-        assertTrue(lastUsedTime != WebappDataStorage.LAST_USED_UNSET);
-        assertTrue(lastUsedTime != WebappDataStorage.LAST_USED_INVALID);
+        assertTrue(lastUsedTime != WebappDataStorage.TIMESTAMP_INVALID);
 
         // Move the last used time one day in the past.
         mSharedPreferences.edit()
                 .putLong(WebappDataStorage.KEY_LAST_USED, lastUsedTime - TimeUnit.DAYS.toMillis(1L))
                 .apply();
         assertTrue(storage.wasLaunchedRecently());
 
         // Move the last used time three days in the past.
         mSharedPreferences.edit()
                 .putLong(WebappDataStorage.KEY_LAST_USED, lastUsedTime - TimeUnit.DAYS.toMillis(3L))
@@ skipping 207 matching lines @@
                 if (actual.getPixel(i, j) != 0) return false;
             }
         }
         return true;
     }
 
     private static Bitmap createBitmap() {
         return Bitmap.createBitmap(1, 1, Bitmap.Config.ARGB_8888);
     }
 }