Add more components unittests to the GN build.

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 e4db8adac4679938597726fe6a5404f7b1554c6e..5e667f816f7510c173453f053ca4f55bdc7f4458 100644
--- a/components/dom_distiller/core/BUILD.gn
+++ b/components/dom_distiller/core/BUILD.gn
@@ -54,7 +54,9 @@ source_set("core") {
   ]
   deps = [
     "//base",
+    "//base:prefs",
     "//components/leveldb_proto",
+    "//components/pref_registry",
     "//components/resources",
     "//components/strings",
     "//net",
@@ -74,7 +76,7 @@ source_set("core") {
 }
 
 # GYP version: components/dom_distiller.gypi:dom_distiller_test_support
-static_library("test_support") {
+source_set("test_support") {
   testonly = true
   sources = [
     "dom_distiller_test_util.cc",
@@ -87,10 +89,12 @@ static_library("test_support") {
 
   deps = [
     ":core",
+    "//base",
     "//components/leveldb_proto:test_support",
     "//sync",
     "//testing/gmock",
     "//testing/gtest",
+    "//url",
   ]
 }
 
@@ -113,8 +117,14 @@ source_set("unit_tests") {
   deps = [
     ":core",
     ":test_support",
+    "//base",
+    "//components/leveldb_proto:test_support",
+    "//components/pref_registry:test_support",
+    "//net:test_support",
+    "//sync",
     "//testing/gmock",
     "//testing/gtest",
+    "//url",
   ]
 }