Never create a "struct point" with a position possibly outside the
device screen (i.e. in the black borders area), and do not transmit such
events.
This fixes an assertion failure on mouse wheel events outside the device
screen area.
To handle special chars, text is handled as text input instead of key
events. However, this breaks the separation of DOWN and UP key events.
As a compromise, send letters and space as key events, to preserve
original DOWN/UP events, but send other text input events as text, to be
able to send "special" characters.
Fixes <https://github.com/Genymobile/scrcpy/issues/87>.
Suggested-by: pete1414
Suggested-by: King-Slide <kingslide@gmail.com>
