Adding some widget addition flow tests

> Added two dummy widget providers: with config and without config
> Added tests for verify widget config flow

Change-Id: I4577f085abe8f8b82047b644c71cc9065358153a

tests/src/com/android/launcher3/testcomponent/WidgetConfigActivity.java

@@ -0,0 +1,64 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy of
+ * the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package com.android.launcher3.testcomponent;
+
+import android.app.Activity;
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.os.Bundle;
+
+/**
+ * Simple activity for widget configuration
+ */
+public class WidgetConfigActivity extends Activity {
+
+    public static final String SUFFIX_FINISH = "-finish";
+    public static final String EXTRA_CODE = "code";
+    public static final String EXTRA_INTENT = "intent";
+
+    private final BroadcastReceiver mFinishReceiver = new BroadcastReceiver() {
+
+        @Override
+        public void onReceive(Context context, Intent intent) {
+            WidgetConfigActivity.this.setResult(
+                    intent.getIntExtra(EXTRA_CODE, RESULT_CANCELED),
+                    (Intent) intent.getParcelableExtra(EXTRA_INTENT));
+            WidgetConfigActivity.this.finish();
+        }
+    };
+
+    private final String mAction = this.getClass().getName();
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        registerReceiver(mFinishReceiver, new IntentFilter(mAction + SUFFIX_FINISH));
+    }
+
+    @Override
+    protected void onResume() {
+        super.onResume();
+        sendBroadcast(new Intent(mAction).putExtra(Intent.EXTRA_INTENT, getIntent()));
+    }
+
+    @Override
+    protected void onDestroy() {
+        unregisterReceiver(mFinishReceiver);
+        super.onDestroy();
+    }
+}