Add more components to "gn check", work on dom_distiller.

components/dom_distiller/core/BUILD.gn

Index: components/dom_distiller/core/BUILD.gn
diff --git a/components/dom_distiller/core/BUILD.gn b/components/dom_distiller/core/BUILD.gn
index fa6c7ba0ff25440d06681dd629264ba57b8aa472..b3e6486e35cf85ea63d0ea13ef4e233f133b9d39 100644
--- a/components/dom_distiller/core/BUILD.gn
+++ b/components/dom_distiller/core/BUILD.gn
@@ -5,8 +5,6 @@
 # GYP version: components/dom_distiller.gypi:dom_distiller_core
 source_set("core") {
   sources = [
-    "../android/component_jni_registrar.cc",
-    "../android/component_jni_registrar.h",
     "article_attachments_data.cc",
     "article_attachments_data.h",
     "article_distillation_update.cc",
@@ -75,7 +73,6 @@ source_set("core") {
     "//net",
     "//skia",
     "//sync",
-    "//sync/protocol",  # TODO(brettw) bug 475091: this should be unnecessary.
     "//third_party/re2",
     "//ui/base",
     "//url",