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

minidump/minidump_writable_test.cc

Index: minidump/minidump_writable_test.cc
diff --git a/minidump/minidump_writable_test.cc b/minidump/minidump_writable_test.cc
index fb52334dbd9389327ce329665c2cab20b9e03e0b..6e345afecb0b39f0b12efac13cb55865857d4b5e 100644
--- a/minidump/minidump_writable_test.cc
+++ b/minidump/minidump_writable_test.cc
@@ -21,10 +21,10 @@
 #include "gtest/gtest.h"
 #include "util/file/string_file_writer.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 class BaseTestMinidumpWritable : public crashpad::internal::MinidumpWritable {
  public:
   BaseTestMinidumpWritable()
@@ -833,3 +833,5 @@ TEST(MinidumpWritable, LocationDescriptor) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad