Expose Add/RemoveActionCallback to java

base/test/android/javatests/src/org/chromium/base/test/util/UserActionTester.java

Index: base/test/android/javatests/src/org/chromium/base/test/util/UserActionTester.java
diff --git a/base/test/android/javatests/src/org/chromium/base/test/util/UserActionTester.java b/base/test/android/javatests/src/org/chromium/base/test/util/UserActionTester.java
new file mode 100644
index 0000000000000000000000000000000000000000..88e3551131f89c82b80e5941fe2ab59ba7b4d201
--- /dev/null
+++ b/base/test/android/javatests/src/org/chromium/base/test/util/UserActionTester.java
@@ -0,0 +1,51 @@
+// 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.base.test.util;
+
+import org.chromium.base.ThreadUtils;
+import org.chromium.base.metrics.RecordUserAction;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * A util class that records UserActions.
+ */
+public class UserActionTester implements RecordUserAction.UserActionCallback {
+    private List<String> mActions;
+
+    public UserActionTester() {
+        mActions = new ArrayList<>();
+        ThreadUtils.runOnUiThreadBlocking(new Runnable() {
+            @Override
+            public void run() {
+                RecordUserAction.setActionCallbackForTesting(UserActionTester.this);
+            }
+        });
+    }
+
+    public void tearDown() {
+        ThreadUtils.runOnUiThreadBlocking(new Runnable() {
+            @Override
+            public void run() {
+                RecordUserAction.removeActionCallbackForTesting();
+            }
+        });
+    }
+
+    @Override
+    public void onActionRecorded(String action) {
+        mActions.add(action);
+    }
+
+    public List<String> getActions() {
+        return mActions;
+    }
+
+    @Override
+    public String toString() {
+        return "Actions: " + mActions.toString();
+    }
+}