Remove the //ios/public/test target.

ios/chrome/browser/BUILD.gn

Index: ios/chrome/browser/BUILD.gn
diff --git a/ios/chrome/browser/BUILD.gn b/ios/chrome/browser/BUILD.gn
index c95a033142461583ffe114fb31ce123cae532f8c..5f6ed31b5a5cd7978e2eb1e3eb8e0bae7b9de98f 100644
--- a/ios/chrome/browser/BUILD.gn
+++ b/ios/chrome/browser/BUILD.gn
@@ -689,6 +689,8 @@ source_set("test_support") {
     "signin/fake_oauth2_token_service_builder.h",
     "signin/fake_signin_manager_builder.cc",
     "signin/fake_signin_manager_builder.h",
+    "sync/fake_sync_service_factory.cc",
+    "sync/fake_sync_service_factory.h",
     "sync/ios_chrome_profile_sync_test_util.cc",
     "sync/ios_chrome_profile_sync_test_util.h",
     "sync/sync_setup_service_mock.cc",
@@ -698,14 +700,19 @@ source_set("test_support") {
   deps = [
     "//base",
     "//components/browser_sync/browser",
+    "//components/keyed_service/core",
+    "//components/keyed_service/ios",
     "//components/signin/core/browser",
     "//components/signin/ios/browser",
     "//components/sync_driver",
+    "//components/sync_driver:test_support",
     "//ios/chrome/browser",
     "//ios/chrome/common",
     "//ios/chrome/test",
     "//ios/public/provider/chrome/browser",
+    "//ios/public/provider/chrome/browser:test_support",
     "//ios/web",
+    "//sync",
     "//testing/gmock",
     "//testing/gtest",
     "//ui/base",