Add AwVariationsSeedFetchService and refactory VariationsSeedFetcher

android_webview/javatests/src/org/chromium/android_webview/test/AwVariationsSeedFetchServiceTest.java

+// Copyright 2017 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.android_webview.test;
+
+import android.annotation.TargetApi;
+import android.os.Build;
+import android.support.test.filters.MediumTest;
+import android.test.InstrumentationTestCase;
+
+import org.chromium.android_webview.AwVariationsSeedFetchService;
+import org.chromium.android_webview.AwVariationsSeedFetchService.SeedPreference;
+import org.chromium.base.ContextUtils;
+import org.chromium.base.annotations.SuppressFBWarnings;
+import org.chromium.components.variations.firstrun.VariationsSeedFetcher.SeedInfo;
+
+import java.io.File;
+import java.io.IOException;
+import java.util.Arrays;
+
+/**
+ * Instrumentation tests for AwVariationsSeedFetchService.
+ */
+@TargetApi(Build.VERSION_CODES.LOLLIPOP) // JobService requires API level 21.
+public class AwVariationsSeedFetchServiceTest extends InstrumentationTestCase {
+    private File mSeedDataFile;
+    private File mSeedPrefFile;
+
+    protected void setUp() throws Exception {
+        ContextUtils.initApplicationContextForTests(
+                getInstrumentation().getTargetContext().getApplicationContext());
+    }
+
+    @SuppressFBWarnings("RV_RETURN_VALUE_IGNORED_BAD_PRACTICE") // ignoring File.delete() return
+    protected void tearDown() throws Exception {
+        if (mSeedDataFile != null) {
+            mSeedDataFile.delete();
+        }
+        if (mSeedPrefFile != null) {
+            mSeedPrefFile.delete();
+        }
+    }
+
+    /**
+     * Ensure reading and writing seed data and pref works correctly.
+     */
+    @MediumTest
+    public void testReadAndWriteSeedData() throws IOException, ClassNotFoundException {
+        SeedInfo seedInfo = new SeedInfo();
+        seedInfo.seedData = "SeedData".getBytes();
+        seedInfo.signature = "SeedSignature";
+        seedInfo.country = "SeedCountry";
+        seedInfo.date = "SeedDate";
+        seedInfo.isGzipCompressed = true;
+        AwVariationsSeedFetchService.storeVariationsSeed(seedInfo);
+
+        File webViewFileDir = AwVariationsSeedFetchService.getOrCreateWebViewVariationsDir();
+        mSeedDataFile = new File(webViewFileDir, AwVariationsSeedFetchService.SEED_DATA_FILENAME);
+        mSeedPrefFile = new File(webViewFileDir, AwVariationsSeedFetchService.SEED_PREF_FILENAME);
+        assertTrue(mSeedDataFile.exists());
+        assertTrue(mSeedPrefFile.exists());

[Alexei Svitkine (slow), 2017/07/18 19:09:40]

I don't think the test needs to check this. It's an implementation detail of the
class.

To clean up data, you should just add a ClearDataForTesting() function to the
class and call that - where the class itself can take care about knowing what
needs to be cleared.

If you do that, you can make getOrCreate*() function private.

[yiyuny, 2017/07/18 21:44:58]

Done.

+
+        byte[] seedData = AwVariationsSeedFetchService.getVariationsSeedData();
+        assertTrue(Arrays.equals(seedData, seedInfo.seedData));
+
+        SeedPreference seedPreference = AwVariationsSeedFetchService.getVariationsSeedPreference();
+        assertEquals(seedPreference.signature, seedInfo.signature);
+        assertEquals(seedPreference.country, seedInfo.country);
+        assertEquals(seedPreference.date, seedInfo.date);
+        assertEquals(seedPreference.isGzipCompressed, seedInfo.isGzipCompressed);
+    }
+}