Replace IPC messages in layout_test_render_frame_observer.

content/shell/common/layout_test.mojom

+// 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.
+
+module content.mojom;
+
+import "mojo/common/file_path.mojom";
+import "ui/gfx/geometry/mojo/geometry.mojom";
+import "url/mojo/url.mojom";
+
+struct ShellTestConfiguration {
+  // The current working directory.
+  mojo.common.mojom.FilePath current_working_directory;
+
+  // The temporary directory of the system.
+  mojo.common.mojom.FilePath temp_path;
+
+  // The URL of the current layout test.
+  url.mojom.Url test_url;
+
+  // True if pixel tests are enabled.
+  bool enable_pixel_dumping;
+
+  // True if tests can open external URLs
+  bool allow_external_pages;
+
+  // The expected MD5 hash of the pixel results.
+  string expected_pixel_hash;
+
+  // The initial size of the test window.
+  gfx.mojom.Size initial_size;
+};
+
+interface LayoutTestControl {
+  // Asks a frame to dump its contents into a string and send them back over
+  // IPC.
+  LayoutDumpRequest();
+
+  // Replicates test config (for an already started test) to a new renderer
+  // that hosts parts of the main test window.
+  ReplicateTestConfiguration(ShellTestConfiguration config);
+
+  // Sets the test config for a layout test that is being started.  This message
+  // is sent only to a renderer that hosts parts of the main test window.
+  SetTestConfiguration(ShellTestConfiguration config);
+
+  // Sets up a secondary renderer (renderer that doesn't [yet] host parts of the
+  // main test window) for a layout test.
+  SetupSecondaryRenderer();
+};