The old grid_reset test expected the complete grid to be reset, but
instead of resetting the whole grid the `grid.scroll_limit` is just set
to `0` now. This leads to the rest of the grid still containing the old
information.
To fix this test it has simply be re-recorded. The new tests now still
contains the complete history but it is checked that the `scroll_limit`
is correctly reset.
In the current scrollback PR the `reset` command does not affect the
scrollback history. To make sure the terminal is properly reset, it
should clear the scrollback history.
This commit fixes this by creating a new and empty grid whenever `reset`
is executed. It takes the current dimensions and history size from the
old grid.
Right now there's an empty ref-test called `grid_reset` without any
content, this should be implemented once #1244 is resolved.
This fixes#1242.
