AndroidOverlay implementation using Dialog.

content/public/android/java/src/org/chromium/content/browser/androidoverlay/DialogOverlayOperations.java

+// 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.content.browser.androidoverlay;
+
+import android.app.Dialog;
+import android.content.Context;
+import android.os.Handler;
+import android.os.IBinder;
+import android.view.Surface;
+
+/**
+ * Common operations needed by DialogOverlayImpl, which are handy to mock out.
+ */
+interface DialogOverlayOperations {
+    interface WindowTokenListener {
+        void onWindowToken(final IBinder token);
+        public void onDismissed();
+    }
+
+    /**
+     * Notify that the overlay has been released by the client.
+     * This will be called on the Browser UI thread.
+     */
+    void notifyReleased();
+
+    /**
+     * Create the dialog.  This will be called on the overlay-ui thread.
+     * @param context The context that we'll provide to the dialog.
+     */
+    Dialog createDialog(Context context);
+
+    /**
+     * Return a Handler that can post tasks to the overlay-ui thread.
+     */
+    Handler getOverlayUiHandler();
+
+    /**
+     * Start receiving window token updates on |listener|.  This may only be called once.
+     * @param token routing token that we'll use to find the window token.
+     * @param listener listener that we'll send updates to.
+     */
+    void registerWindowTokenListener(
+            org.chromium.mojo.common.mojom.UnguessableToken token, WindowTokenListener listener);
+
+    /**
+     * Unregister the current listener.
+     */
+    void unregisterWindowTokenListener();
+
+    /**
+     * Register a surface and return the surface id for it.
+     * @param surface Surface that we should register.
+     * @return surface id that we associated with |surface|.
+     */
+    int registerSurface(Surface surface);
+    void unregisterSurface(int surfaceId);
+}