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

util/mac/mach_o_image_reader_test.cc

Index: util/mac/mach_o_image_reader_test.cc
diff --git a/util/mac/mach_o_image_reader_test.cc b/util/mac/mach_o_image_reader_test.cc
index 2991cc5f0996e061e0d6d277ccbd083028e47aa7..f174a4ea03da12b18f099f8bd4bf50c60a6e5603 100644
--- a/util/mac/mach_o_image_reader_test.cc
+++ b/util/mac/mach_o_image_reader_test.cc
@@ -36,10 +36,10 @@
 // This file is responsible for testing MachOImageReader,
 // MachOImageSegmentReader, and MachOImageSymbolTableReader.
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 // Native types and constants, in cases where the 32-bit and 64-bit versions
 // are different.
 #if defined(ARCH_CPU_64_BITS)
@@ -659,3 +659,5 @@ TEST(MachOImageReader, Self_DyldImages) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad