Replace IPC messages in layout_test_render_frame_observer.

content/shell/common/layout_test.mojom

Index: content/shell/common/layout_test.mojom
diff --git a/content/shell/common/layout_test.mojom b/content/shell/common/layout_test.mojom
new file mode 100644
index 0000000000000000000000000000000000000000..5e87bb4957320296ea6c0e4235e684d391cf4e3b
--- /dev/null
+++ b/content/shell/common/layout_test.mojom
@@ -0,0 +1,25 @@
+// 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;
+
+[Native]
+struct ShellTestConfig;
+
+interface LayoutTestControl {
+  // Asks a frame to dump its contents into a string and send them back over IPC.

[tibell, 2017/01/20 01:55:18]

<80 chars

You can try to run "git cl format" and see if it detects any other style issues
(although I don't think it yet works on mojom files).

[Jia, 2017/01/20 02:54:33]

Done. It indeed doesn't work on mojoms yet, but I've run git-cl format to format
other files, thanks!

+  LayoutDumpRequest();
+
+  // Replicates test config (for an already started test) to a new renderer
+  // that hosts parts of the main test window.
+  ReplicateTestConfiguration(ShellTestConfig 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(ShellTestConfig config);
+
+  // Sets up a secondary renderer (renderer that doesn't [yet] host parts of the
+  // main test window) for a layout test.
+  SetupSecondaryRenderer();
+};