Replace IPC messages in layout_test_render_frame_observer.

content/shell/BUILD.gn

Index: content/shell/BUILD.gn
diff --git a/content/shell/BUILD.gn b/content/shell/BUILD.gn
index 6749acd82ed5b109af1f277028acb934736509b1..8329330263c636fbc0e3cdca0052894df8203c67 100644
--- a/content/shell/BUILD.gn
+++ b/content/shell/BUILD.gn
@@ -162,6 +162,8 @@ static_library("content_shell_lib") {
     "common/shell_messages.h",
     "common/shell_origin_trial_policy.cc",
     "common/shell_origin_trial_policy.h",
+    "common/shell_param_traits.cc",
+    "common/shell_param_traits.h",
     "common/shell_switches.cc",
     "common/shell_switches.h",
     "common/shell_test_configuration.cc",
@@ -760,6 +762,11 @@ if (is_mac) {
 
 mojom("mojo_bindings") {
   sources = [
+    "common/layout_test.mojom",
     "common/layout_test/layout_test_bluetooth_fake_adapter_setter.mojom",
   ]
+  public_deps = [
+    "//ui/gfx/geometry/mojo",
+    "//url/mojo:url_mojom_gurl",
+  ]
 }