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

util/mac/mach_o_image_segment_reader_test.cc

Index: util/mac/mach_o_image_segment_reader_test.cc
diff --git a/util/mac/mach_o_image_segment_reader_test.cc b/util/mac/mach_o_image_segment_reader_test.cc
index 226eaa0715f15b7f14c575c2f0183b3cb0b1b467..d0e706f8b7121ff177b84769721bdd6208fc46d7 100644
--- a/util/mac/mach_o_image_segment_reader_test.cc
+++ b/util/mac/mach_o_image_segment_reader_test.cc
@@ -20,10 +20,10 @@
 #include "base/strings/stringprintf.h"
 #include "gtest/gtest.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 // Most of MachOImageSegmentReader is tested as part of MachOImageReader, which
 // depends on MachOImageSegmentReader to provide major portions of its
 // functionality. Because MachOImageSegmentReader is difficult to use except by
@@ -184,3 +184,5 @@ TEST(MachOImageSegmentReader, SegmentAndSectionNameString) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad