message: tests: Remove redundant coverage test
  The only point was to try to test all paths where we can run out of
  memory while decoding something. It seems like it may be impossible to
  actually do this given that we can't run all paths as wchar_t size
  detection is done at runtime...
diff: @@ -965,17 +965,6 @@ TEST(parse_out_of_memory_conversion)
  CHECK(!doc.first_child());
  }
  -#ifdef PUGIXML_WCHAR_MODE
  -TEST(parse_out_of_memory_conversion_wchar)
  -{
  - test_runner::_memory_fail_threshold = 1;
  -
  - xml_document doc;
  - CHECK_ALLOC_FAIL(CHECK(doc.load_buffer("<foo />", 7).status == status_out_of_memory));
  - CHECK(!doc.first_child());
  -}
  -#endif
  -
  TEST(parse_out_of_memory_allocator_state_sync)
  {
  const unsigned int count = 10000;
  