Don’t use using directives (“using namespace”) in tests

util/test/multiprocess_exec_test.cc

Index: util/test/multiprocess_exec_test.cc
diff --git a/util/test/multiprocess_exec_test.cc b/util/test/multiprocess_exec_test.cc
index 2f30b9b038450dce53a7b8c3931c060e6500dc65..d70f0d06a36454dc593eb030519fde903d17bcf9 100644
--- a/util/test/multiprocess_exec_test.cc
+++ b/util/test/multiprocess_exec_test.cc
@@ -21,11 +21,10 @@
 #include "util/file/fd_io.h"
 #include "util/test/executable_path.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-using namespace crashpad::test;
-
 class TestMultiprocessExec final : public MultiprocessExec {
  public:
   TestMultiprocessExec() : MultiprocessExec() {}
@@ -54,3 +53,5 @@ TEST(MultiprocessExec, MultiprocessExec) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad