Extract ScopedTestNSSDB from nss_util.

crypto/BUILD.gn

Index: crypto/BUILD.gn
diff --git a/crypto/BUILD.gn b/crypto/BUILD.gn
index 307842084cb20418010cc3439c0f5a8f02321458..340e0ffa8d6e0bfc9e47fee8bafda15246bbb045 100644
--- a/crypto/BUILD.gn
+++ b/crypto/BUILD.gn
@@ -91,6 +91,7 @@ component("crypto") {
 
   deps = [
     ":platform",
+    ":test_support",
     "//base",
     "//base/third_party/dynamic_annotations",
   ]
@@ -131,6 +132,7 @@ component("crypto") {
       "hmac_nss.cc",
       "nss_util.cc",
       "nss_util.h",
+      "nss_util_internal.h",
       "rsa_private_key_nss.cc",
       "secure_hash_default.cc",
       "signature_creator_nss.cc",
@@ -237,6 +239,37 @@ test("crypto_unittests") {
   ]
 }
 
+source_set("test_support") {
+  sources = [
+    'scoped_test_nss_db.cc',
+    'scoped_test_nss_db.h',
+    'scoped_test_nss_chromeos_user.cc',
+    'scoped_test_nss_chromeos_user.h',
+    'scoped_test_system_nss_key_slot.cc',
+    'scoped_test_system_nss_key_slot.h',
+  ]
+  deps = [
+    ":crypto",
+    "//base",
+  ]
+
+  if (!use_nss_certs) {
+    sources -= [
+      'scoped_test_nss_db.cc',
+      'scoped_test_nss_db.h',
+    ]
+  }
+
+  if (!is_chromeos) {
+    sources -= [
+      'scoped_test_nss_chromeos_user.cc',
+      'scoped_test_nss_chromeos_user.h',
+      'scoped_test_system_nss_key_slot.cc',
+      'scoped_test_system_nss_key_slot.h',
+    ]
+  }
+}
+
 # This is a meta-target that forwards to NSS's SSL library or OpenSSL,
 # according to the state of the crypto flags. A target just wanting to depend
 # on the current SSL library should just depend on this.