message: matdbg: call GLSLTools init / shutdown.
diff: #include <backend/DriverEnums.h>
  +#include "sca/GLSLTools.h"
  +
  #include <sstream>
  #include <string>
  @@ -514,9 +516,11 @@ DebugServer::DebugServer(Backend backend, int port) : mBackend(backend) {
  mServer->addWebSocketHandler("", mWebSocketHandler);
  slog.i << "DebugServer listening at http://localhost:" << port << io::endl;
  + filamat::GLSLTools::init();
  }
  DebugServer::~DebugServer() {
  + filamat::GLSLTools::shutdown();
  for (auto& pair : mMaterialRecords) {
  delete [] pair.second.package;
  }
  