Add a mojo channel for frame messages.

content/browser/BUILD.gn

 # Copyright 2014 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.
 
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//gpu/vulkan/features.gni")
 import("//media/media_options.gni")
 import("//ppapi/features/features.gni")
 import("//printing/features/features.gni")
@@ skipping 674 matching lines @@
     "frame_host/form_submission_throttle.cc",
     "frame_host/form_submission_throttle.h",
     "frame_host/frame_navigation_entry.cc",
     "frame_host/frame_navigation_entry.h",
     "frame_host/frame_tree.cc",
     "frame_host/frame_tree.h",
     "frame_host/frame_tree_node.cc",
     "frame_host/frame_tree_node.h",
     "frame_host/frame_tree_node_blame_context.cc",
     "frame_host/frame_tree_node_blame_context.h",
+    "frame_host/input/legacy_ipc_frame_input_handler.cc",
+    "frame_host/input/legacy_ipc_frame_input_handler.h",
     "frame_host/interstitial_page_impl.cc",
     "frame_host/interstitial_page_impl.h",
     "frame_host/interstitial_page_navigator_impl.cc",
     "frame_host/interstitial_page_navigator_impl.h",
     "frame_host/mixed_content_navigation_throttle.cc",
     "frame_host/mixed_content_navigation_throttle.h",
     "frame_host/navigation_controller_android.cc",
     "frame_host/navigation_controller_android.h",
     "frame_host/navigation_controller_delegate.h",
     "frame_host/navigation_controller_impl.cc",
@@ skipping 1436 matching lines @@
   if (!is_component_build) {
     public_deps = [
       ":browser",
     ]
   } else {
     public_deps = [
       "//third_party/leveldatabase",
     ]
   }
 }