Enable variations restrict param for Java-side fetches.

chrome/android/junit/src/org/chromium/chrome/browser/metrics/VariationsSessionTest.java

Index: chrome/android/junit/src/org/chromium/chrome/browser/metrics/VariationsSessionTest.java
diff --git a/chrome/android/junit/src/org/chromium/chrome/browser/metrics/VariationsSessionTest.java b/chrome/android/junit/src/org/chromium/chrome/browser/metrics/VariationsSessionTest.java
new file mode 100644
index 0000000000000000000000000000000000000000..4afaf1f6e8b744ac0770e45e7a4d0191ef7f5984
--- /dev/null
+++ b/chrome/android/junit/src/org/chromium/chrome/browser/metrics/VariationsSessionTest.java
@@ -0,0 +1,78 @@
+// 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.chrome.browser.metrics;
+
+import android.content.Context;
+
+import static org.mockito.Mockito.any;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.spy;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.robolectric.annotation.Config;
+
+import org.chromium.base.Callback;
+import org.chromium.base.ContextUtils;
+import org.chromium.testing.local.LocalRobolectricTestRunner;
+
+/**
+ * Tests for VariationsSession
+ */
+@RunWith(LocalRobolectricTestRunner.class)
+@Config(manifest = Config.NONE)
+public class VariationsSessionTest {
+    private TestVariationsSession mSession;
+
+    private static class TestVariationsSession extends VariationsSession {
+        private Callback<String> mCallback;
+
+        @Override
+        protected void getRestrictMode(Context context, Callback<String> callback) {
+            mCallback = callback;
+        }
+
+        public void runCallback(String value) {
+            mCallback.onResult(value);
+        }
+
+        @Override
+        protected void nativeStartVariationsSession(String restrictMode) {
+            // No-op for tests.
+        }
+    }
+
+    @Before
+    public void setUp() {
+        mSession = spy(new TestVariationsSession());
+    }
+
+    @Test
+    public void testStart() {
+        mSession.start(ContextUtils.getApplicationContext());
+        verify(mSession, never()).nativeStartVariationsSession(any(String.class));
+
+        String restrictValue = "test";
+        mSession.runCallback(restrictValue);
+        verify(mSession, times(1)).nativeStartVariationsSession(restrictValue);
+    }
+
+    @Test
+    public void testGetRestrictModeValue() {
+        mSession.getRestrictModeValue(ContextUtils.getApplicationContext(), new Callback<String>() {
+            @Override
+            public void onResult(String restrictMode) {}
+        });
+        String restrictValue = "test";
+        mSession.runCallback(restrictValue);
+        verify(mSession, never()).nativeStartVariationsSession(any(String.class));
+
+        mSession.start(ContextUtils.getApplicationContext());
+        verify(mSession, times(1)).nativeStartVariationsSession(restrictValue);
+    }
+}