Remove dependence on a message loop for net::PathBuilder.

net/tools/cert_verify_tool/cert_verify_tool.cc

Index: net/tools/cert_verify_tool/cert_verify_tool.cc
diff --git a/net/tools/cert_verify_tool/cert_verify_tool.cc b/net/tools/cert_verify_tool/cert_verify_tool.cc
index a9c21fc69525956cf2e855990dd429ec90d4afb9..78e10bfa86297c19738b3e8b32fd0ae75142fca4 100644
--- a/net/tools/cert_verify_tool/cert_verify_tool.cc
+++ b/net/tools/cert_verify_tool/cert_verify_tool.cc
@@ -69,6 +69,7 @@ void PrintUsage(const char* argv0) {
 
 int main(int argc, char** argv) {
   base::AtExitManager at_exit_manager;
+  // TODO(eroman): Is this needed?
   base::MessageLoopForIO message_loop;
   if (!base::CommandLine::Init(argc, argv)) {
     std::cerr << "ERROR in CommandLine::Init\n";