message: Add error message for CHECK failure.
diff: @@ -58,7 +58,8 @@ Compiler::GetPlatformCompilers() {
  LazyInitMutex();
  tensorflow::mutex_lock lock(*platform_compiler_mutex_);
  auto* factories = GetPlatformCompilerFactories();
  - CHECK(factories->find(platform_id) == factories->end());
  + CHECK(factories->find(platform_id) == factories->end())
  + << "Compiler factory already registered for platform";
  (*factories)[platform_id] = std::move(compiler_factory);
  }
  