Remove the //ios/public/test target.

ios/public/provider/chrome/browser/BUILD.gn

 # Copyright 2015 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.
 
 source_set("browser") {
   sources = [
     "browser_state/chrome_browser_state.cc",
     "browser_state/chrome_browser_state.h",
     "browser_state/chrome_browser_state_manager.h",
     "chrome_browser_provider.cc",
@@ skipping 14 matching lines @@
     "updatable_resource_provider.mm",
   ]
 
   deps = [
     "//base",
     "//components/autofill/core/browser",
     "//ios/public/provider/web",
     "//ios/web",
   ]
 }
+
+source_set("test_support") {
+  testonly = true
+
+  sources = [
+    "test_chrome_browser_provider.h",
+    "test_chrome_browser_provider.mm",
+    "test_chrome_provider_initializer.cc",
+    "test_chrome_provider_initializer.h",
+    "test_updatable_resource_provider.h",
+    "test_updatable_resource_provider.mm",
+  ]
+
+  deps = [
+    ":browser",
+    "//base",
+    "//components/signin/ios/browser:test_support",
+    "//testing/gtest",
+  ]
+}