Add missing header files to GN files

content/public/browser/BUILD.gn

Index: content/public/browser/BUILD.gn
diff --git a/content/public/browser/BUILD.gn b/content/public/browser/BUILD.gn
index b998e724705d5f14a499f243fa728d05ddd01bca..8fb942e05fc6db5e51aee277314d0979633393c5 100644
--- a/content/public/browser/BUILD.gn
+++ b/content/public/browser/BUILD.gn
@@ -92,6 +92,7 @@ source_set("browser_sources") {
     "devtools_agent_host_observer.h",
     "devtools_external_agent_proxy.h",
     "devtools_external_agent_proxy_delegate.h",
+    "devtools_frontend_host.h",
     "devtools_manager_delegate.cc",
     "devtools_manager_delegate.h",
     "devtools_socket_factory.h",
@@ -121,6 +122,7 @@ source_set("browser_sources") {
     "gpu_service_registry.h",
     "gpu_utils.cc",
     "gpu_utils.h",
+    "guest_host.h",
     "guest_mode.cc",
     "guest_mode.h",
     "histogram_fetcher.h",
@@ -139,6 +141,7 @@ source_set("browser_sources") {
     "media_capture_devices.h",
     "media_device_id.cc",
     "media_device_id.h",
+    "media_request_state.h",
     "media_session.h",
     "media_session_observer.cc",
     "media_session_observer.h",
@@ -194,12 +197,14 @@ source_set("browser_sources") {
     "push_messaging_service.h",
     "quota_permission_context.h",
     "readback_types.h",
+    "reload_type.h",
     "render_frame_host.h",
     "render_process_host.h",
     "render_process_host_factory.h",
     "render_process_host_observer.h",
     "render_view_host.h",
     "render_widget_host.h",
+    "render_widget_host_iterator.h",
     "render_widget_host_view.h",
     "render_widget_host_view_mac_delegate.h",
     "resource_context.h",
@@ -213,6 +218,7 @@ source_set("browser_sources") {
     "resource_request_info.h",
     "resource_throttle.cc",
     "resource_throttle.h",
+    "restore_type.h",
     "save_page_type.h",
     "screen_orientation_delegate.h",
     "security_style_explanation.h",
@@ -247,6 +253,7 @@ source_set("browser_sources") {
     "url_data_source.cc",
     "url_data_source.h",
     "utility_process_host.h",
+    "utility_process_host_client.h",
     "utility_process_mojo_client.h",
     "vpn_service_proxy.h",
     "web_contents.cc",