Rename spec -> test

'Test' is a lot more straightforward of a name.

test/helpers/record_alloc.h

@@ -0,0 +1,16 @@
+#ifndef HELPERS_RECORD_ALLOC_H_
+#define HELPERS_RECORD_ALLOC_H_
+
+#include <set>
+
+namespace record_alloc {
+
+void start();
+void stop();
+void fail_at_allocation_index(size_t failure_index);
+std::set<size_t> outstanding_allocation_indices();
+size_t allocation_count();
+
+}  // namespace record_alloc
+
+#endif  // HELPERS_RECORD_ALLOC_H_