gfe-relnote: n/a(test only) more portability improvement to SimpleLinkedHashMap.
gfe-relnote: n/a(test only) more portability improvement to
SimpleLinkedHashMap.

PiperOrigin-RevId: 245763701
Change-Id: I1a266f6949b05ffcf3ceef8e9917ccc70bab0bc5

google/quiche,google/quiche,google/quiche,google/quiche