Upstream VariationsSession

chrome/android/java/src/org/chromium/chrome/browser/metrics/VariationsSession.java

Index: chrome/android/java/src/org/chromium/chrome/browser/metrics/VariationsSession.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/metrics/VariationsSession.java b/chrome/android/java/src/org/chromium/chrome/browser/metrics/VariationsSession.java
new file mode 100644
index 0000000000000000000000000000000000000000..c6f763cf78d8c694e684464696a5304e8cfc9243
--- /dev/null
+++ b/chrome/android/java/src/org/chromium/chrome/browser/metrics/VariationsSession.java
@@ -0,0 +1,39 @@
+// 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.metrics;
+
+import android.content.Context;
+
+/**
+ * Sets up communication with the VariationsService. This is primarily used for
+ * triggering seed fetches on application startup.
+ */
+public class VariationsSession {
+    private boolean mInitialized;
+    private String mRestrictMode;
+
+    /**
+     * Triggers to the native VariationsService that the application has entered the foreground.
+     */
+    public void start(Context context) {
+        if (!mInitialized) {
+            mInitialized = true;
+            // Check the restrict mode only once initially to avoid doing extra work each time the
+            // app enters foreground.
+            mRestrictMode = getRestrictMode(context);
+        }
+        nativeStartVariationsSession(mRestrictMode);
+    }
+
+    /**
+     * Returns the value of the "restrict" URL param that the variations service should use for
+     * variation seed requests.
+     */
+    protected String getRestrictMode(Context context) {
+        return "";
+    }
+
+    private native void nativeStartVariationsSession(String restrictMode);
+}