hterm: Handle clearing screen when not scrolled to bottom

TEST=did the following:
- ls -l a bunch of times to make a long scroll buffer (> 2x term height)
- scroll to top
- Ctrl-Shift-K to clear screen

Change-Id: I74345b7c6cc9deef82766ee2d6c7dbc6f306e86d
Reviewed-by: Robert Ginda <>
Commit-Queue: Andrew de los Reyes <>
Tested-by: Andrew de los Reyes <>
2 files changed
tree: 1c0985edb495b48269e25df299f3c9dc426f9e5d
  1. crosh_builtin/
  2. hterm/
  3. libdot/
  4. nassh/