Sync remaining components_unittests with GN

components/os_crypt/BUILD.gn

 # Copyright 2014 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("os_crypt") {
   sources = [
     "ie7_password_win.cc",
     "ie7_password_win.h",
     "keychain_password_mac.h",
     "keychain_password_mac.mm",
@@ skipping 17 matching lines @@
     sources -= [ "os_crypt_posix.cc" ]
   }
 
   if (is_ios) {
     sources += [
       "keychain_password_mac.mm",
       "os_crypt_mac.mm",
     ]
   }
 }
+
+source_set("unit_tests") {
+  testonly = true
+  sources = [
+    "ie7_password_win_unittest.cc",
+    "keychain_password_mac_unittest.mm",
+    "os_crypt_unittest.cc",
+  ]
+  deps = [
+    ":os_crypt",
+    "//base",
+    "//testing/gtest",
+  ]
+}