Test: tick test cases depends on the environment's font

The multiple line tick test cases depend on the font of the system and cause problem on some machines. So we can improve it by making assertion values with same algorithms of the implementation.

Locate the multiple-line tick test cases and the implementation's tick-layout algorithm. Compare how the tests currently derive their assertion values, then make the assertions independent of the system font. Run the tick tests in environments with different fonts to confirm they pass consistently.

Written by the indexing model from the issue text.