)

…df5_1_14_5_update

In H5F__accum_reset(), when H5F__accum_flush() failed, the freeing of
f_sh->accum.buf was never reached, causing resource leak.

@fortnern added the third argument to H5F__accum_reset() so we can free
f_sh->accum.buf when we close the file, that is, when H5F__accum_reset()
is called from the H5F__dest() route, and can leave the accumulator in place
otherwise.

H5LTfind_dataset() returns true for non-existing datasets because it only compares up to the length of the searched string, such as "Day" vs "DayNight" (issue HDFGroupGH-4780).

This PR applied the user's patch and added tests.