Download Griffin seed on first launch.

android/java/apk_for_test.flags

@@ -634,6 +634,9 @@
 }
 
 -keep class org.chromium.components.variations.firstrun.VariationsSeedFetcher {
+    *** sLock;
+    *** DEFAULT_VARIATIONS_SERVER_URL;
+    *** DEFAULT_FAST_VARIATIONS_SERVER_URL;
     *** get(...);
 }
 

android/javatests/org/chromium/chrome/browser/BytecodeTest.java

@@ -1017,6 +1017,15 @@ public void testFieldsExist() throws Exception {
         Assert.assertTrue(fieldExists(
                 "org/chromium/components/browser_ui/site_settings/SingleWebsiteSettings", "mSite",
                 true, Website.class));
+        Assert.assertTrue(
+                fieldExists("org/chromium/components/variations/firstrun/VariationsSeedFetcher",
+                        "sLock", true, Object.class));
+        Assert.assertTrue(
+                fieldExists("org/chromium/components/variations/firstrun/VariationsSeedFetcher",
+                        "DEFAULT_VARIATIONS_SERVER_URL", true, String.class));
+        Assert.assertTrue(
+                fieldExists("org/chromium/components/variations/firstrun/VariationsSeedFetcher",
+                        "DEFAULT_FAST_VARIATIONS_SERVER_URL", true, String.class));
         Assert.assertTrue(
                 fieldExists("org/chromium/chrome/browser/omnibox/suggestions/AutocompleteMediator",
                         "mNativeInitialized", true, boolean.class));
@@ -1220,8 +1229,9 @@ private boolean fieldExists(
             if (f.getName().equals(fieldName)) {
                 if (checkTypes) {
                     if (fieldType != null && f.getType().equals(fieldType)) return true;
-                } else
+                } else {
                     return true;
+                }
             }
         }
         return false;

build/android/bytecode/bytecode_rewriter.gni

@@ -14,6 +14,7 @@ brave_bytecode_jars = [
   "obj/brave/browser/ui/android/omnibox/java.javac.jar",
   "obj/brave/browser/ui/android/theme/java.javac.jar",
   "obj/brave/components/browser_ui/site_settings/android/java.javac.jar",
+  "obj/brave/components/variations/android/java.javac.jar",
   "obj/chrome/android/base_module_java.javac.jar",
   "obj/chrome/android/chrome_java.javac.jar",
   "obj/chrome/android/features/tab_ui/java.javac.jar",
@@ -39,6 +40,7 @@ brave_bytecode_jars = [
   "obj/components/external_intents/android/java.javac.jar",
   "obj/components/permissions/android/java.javac.jar",
   "obj/components/sync/android/sync_java.javac.jar",
+  "obj/components/variations/android/variations_java.javac.jar",
 ]
 
 template("brave_bytecode_rewriter") {

build/android/bytecode/java/org/brave/bytecode/BraveVariationsSeedFetcherClassAdapter.java

@@ -18,5 +18,12 @@ public BraveVariationsSeedFetcherClassAdapter(ClassVisitor visitor) {
 
         changeMethodOwner(
                 sVariationsSeedFetcherClassName, "get", sBraveVariationsSeedFetcherClassName);
+
+        deleteField(sBraveVariationsSeedFetcherClassName, "sLock");
+        makeProtectedField(sVariationsSeedFetcherClassName, "sLock");
+        deleteField(sBraveVariationsSeedFetcherClassName, "DEFAULT_VARIATIONS_SERVER_URL");
+        makeProtectedField(sVariationsSeedFetcherClassName, "DEFAULT_VARIATIONS_SERVER_URL");
+        deleteField(sBraveVariationsSeedFetcherClassName, "DEFAULT_FAST_VARIATIONS_SERVER_URL");
+        makeProtectedField(sVariationsSeedFetcherClassName, "DEFAULT_FAST_VARIATIONS_SERVER_URL");
     }
 }

components/variations/BUILD.gn

@@ -3,16 +3,9 @@
 # License, v. 2.0. If a copy of the MPL was not distributed with this file,
 # You can obtain one at http://mozilla.org/MPL/2.0/.
 
+import("//brave/components/variations/buildflags.gni")
 import("//build/buildflag_header.gni")
 
-declare_args() {
-  brave_variations_server_url = ""
-}
-
-if (is_official_build) {
-  assert(brave_variations_server_url != "")
-}
-
 buildflag_header("buildflags") {
   header = "buildflags.h"
   flags = [ "BRAVE_VARIATIONS_SERVER_URL=\"$brave_variations_server_url\"" ]

components/variations/android/BUILD.gn

@@ -1,7 +1,9 @@
-# Copyright 2022 The Brave Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
+# Copyright (c) 2022 The Brave Authors. All rights reserved.
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this file,
+# You can obtain one at https://mozilla.org/MPL/2.0/.
 
+import("//brave/components/variations/buildflags.gni")
 import("//build/config/android/rules.gni")
 
 android_library("java") {
@@ -12,4 +14,11 @@ android_library("java") {
     "//components/variations/android:variations_java",
     "//third_party/androidx:androidx_annotation_annotation_java",
   ]
+  srcjar_deps = [ ":brave_variations_config_java" ]
+}
+
+java_cpp_template("brave_variations_config_java") {
+  sources = [ "java/src/org/chromium/components/variations/firstrun/BraveVariationsConfig.template" ]
+  defines =
+      [ "BRAVE_ANDROID_VARIATIONS_SERVER_URL=\"$brave_variations_server_url\"" ]
 }

components/variations/android/java/src/org/chromium/components/variations/firstrun/BraveVariationsConfig.template

@@ -0,0 +1,13 @@
+/* Copyright (c) 2023 The Brave Authors. All rights reserved.
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+package org.chromium.components.variations.firstrun;
+
+/**
+ *  Brave Variations configuration.
+ */
+public class BraveVariationsConfig {
+  public static final String VARIATIONS_SERVER_URL = BRAVE_ANDROID_VARIATIONS_SERVER_URL;
+}

components/variations/android/java/src/org/chromium/components/variations/firstrun/BraveVariationsSeedFetcher.java

@@ -8,16 +8,25 @@
 import androidx.annotation.VisibleForTesting;
 
 import org.chromium.base.CommandLine;
+import org.chromium.base.Log;
 import org.chromium.components.variations.VariationsSwitches;
 
 public class BraveVariationsSeedFetcher extends VariationsSeedFetcher {
+    // To delete in bytecode. Variables from the parent class will be used instead.
+    private static Object sLock;
+    private static String DEFAULT_VARIATIONS_SERVER_URL;
+    private static String DEFAULT_FAST_VARIATIONS_SERVER_URL;
+
     private static VariationsSeedFetcher sInstance;
+    private static final String TAG = "BraveVariations";
 
     public static VariationsSeedFetcher get() {
-        if (sInstance == null) {
-            sInstance = new BraveVariationsSeedFetcher();
+        synchronized (sLock) {
+            if (sInstance == null) {
+                sInstance = new BraveVariationsSeedFetcher();
+            }
+            return sInstance;
         }
-        return sInstance;
     }
 
     @VisibleForTesting
@@ -28,18 +37,29 @@ public BraveVariationsSeedFetcher() {
     @VisibleForTesting
     @Override
     protected String getConnectionString(SeedFetchParameters params) {
-        if (!CommandLine.getInstance().hasSwitch(VariationsSwitches.VARIATIONS_SERVER_URL)) {
-            // If there is no alternative variations server specified, we still don't want to
-            // connect to Google's server.
-            return "";
+        String urlString = super.getConnectionString(params);
+
+        // Fix channel name.
+        urlString = urlString.replaceAll("=canary", "=nightly");
+
+        // Return as is if URL was passed manually.
+        if (CommandLine.getInstance().hasSwitch(VariationsSwitches.VARIATIONS_SERVER_URL)) {
+            return urlString;
         }
 
-        String urlString = super.getConnectionString(params);
-        // Relacing Google's variations server with ours, but keep parameters.
-        int paramsPosition = urlString.indexOf("?", 0);
-        urlString =
-                CommandLine.getInstance().getSwitchValue(VariationsSwitches.VARIATIONS_SERVER_URL)
-                + (paramsPosition > 0 ? urlString.substring(paramsPosition) : "");
+        // Replace Chromium URL with Brave URL.
+        if (urlString.indexOf(DEFAULT_VARIATIONS_SERVER_URL) != -1) {
+            urlString = urlString.replaceFirst(
+                    DEFAULT_VARIATIONS_SERVER_URL, BraveVariationsConfig.VARIATIONS_SERVER_URL);
+        } else if (urlString.indexOf(DEFAULT_FAST_VARIATIONS_SERVER_URL) != -1) {
+            urlString = urlString.replaceFirst(DEFAULT_FAST_VARIATIONS_SERVER_URL,
+                    BraveVariationsConfig.VARIATIONS_SERVER_URL);
+        } else {
+            Log.e(TAG, "Cannot replace seed URL to fetch variations: %s", urlString);
+            urlString = "";
+        }
+
+        Log.i(TAG, "Fetching variations from: %s", urlString);
         return urlString;
     }
 }

components/variations/buildflags.gni

@@ -0,0 +1,12 @@
+# Copyright (c) 2023 The Brave Authors. All rights reserved.
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this file,
+# You can obtain one at https://mozilla.org/MPL/2.0/.
+
+declare_args() {
+  brave_variations_server_url = ""
+}
+
+if (is_official_build) {
+  assert(brave_variations_server_url != "")
+}

test/BUILD.gn

@@ -1279,6 +1279,7 @@ if (is_android) {
       "//components/permissions/android:java",
       "//components/search_engines/android:java",
       "//components/sync/android:sync_java",
+      "//components/variations/android:variations_java",
       "//content/public/android:content_full_java",
       "//third_party/androidx:androidx_appcompat_appcompat_java",
       "//third_party/androidx:androidx_preference_preference_java",