rememberOldPasswordTimes: add unit test

This commit adds several test cases for |rememberOldPasswordTimes|.

Tested: unit test passed.

Overall coverage rate:
  lines......: 79.2% (1809 of 2283 lines)
  functions..: 92.8% (361 of 389 functions)
  branches...: 32.4% (2852 of 8814 branches)

Signed-off-by: Nan Zhou <nanzhoumails@gmail.com>
Change-Id: Iea033026b79a81d67dfb3d513eb951b0b6cb21b6
1 file changed