Problem description
On a Chromebook (with a hardware keyboard), typing Ctrl-Space does nothing.

This particular key-combination is traditionally bound to the set-mark command in Emacs, and so is very heavily used by most users. set-mark is also available via Ctrl-2 (and of course may be bound by the user to something else), but I think for many users, this is inconvenient, (1) because Ctrl-2 is a bit harder to type, (2) because the documentation says to use "C-SPC", and (3) most importantly, because many users have strongly developed muscle memory telling them to hit Ctrl-Space for this command.

This may be related to the fact that in most context on ChromeOS, Ctrl-Space toggles the current input method. However, this is not useful for Termux, as ChromeOS input methods are ignored (whether this is a bug or not is another question).

Other apps in ChromeOS (e.g. the ssh app) successfully use Ctrl-Space for their own use (ssh just passes it through the the connection), so it's definitely possible to override ChromeOS's default behavior for this key-combination (of course it's possible that Android apps in ChromeOS have unique constraints).

Steps to reproduce
Open Termux, run some program where Ctrl-Space should have an effect (e.g., Emacs), type Ctrl-Space. Nothing happens.

Expected behavior
Ctrl-Space should result in some sort of key sequence on the terminal. I think traditionally, Ctrl-Space yielded the same result as Ctrl-2 / Ctrl-Shift-@, but basically anything would be OK as long as it's possible for the user program to see the event.

Additional information
Updatable packages:
apt/stable 1.4.9-19 i686 [upgradable from: 1.4.9-15]
bash/stable 5.0.11 i686 [upgradable from: 5.0.9]
binutils/stable 2.33.1 i686 [upgradable from: 2.32-5]
ca-certificates/stable 20191016 all [upgradable from: 20190515]
clang/stable 9.0.0 i686 [upgradable from: 8.0.1]
command-not-found/stable 1.42 i686 [upgradable from: 1.39]
coreutils/stable 8.31-8 i686 [upgradable from: 8.31-7]
curl/stable 7.66.0-1 i686 [upgradable from: 7.65.3-6]
dos2unix/stable 7.4.1 i686 [upgradable from: 7.4.0-1]
emacs/stable 26.3-1 i686 [upgradable from: 26.3]
findutils/stable 4.7.0 i686 [upgradable from: 4.6.0-4]
gdb/stable 8.3.1 i686 [upgradable from: 8.3-4]
glib/stable 2.60.7 i686 [upgradable from: 2.60.6-1]
gnutls/stable 3.6.10 i686 [upgradable from: 3.6.9-1]
libandroid-support/stable 25-2 i686 [upgradable from: 25-1]
libcurl/stable 7.66.0-1 i686 [upgradable from: 7.65.3-6]
libexpat/stable 2.2.9 i686 [upgradable from: 2.2.7-1]
libffi/stable 3.2.1-5 i686 [upgradable from: 3.2.1-4]
libgcrypt/stable 1.8.5 i686 [upgradable from: 1.8.4-1]
libgnutls/stable 3.6.10 i686 [upgradable from: 3.6.9-1]
libllvm/stable 9.0.0 i686 [upgradable from: 8.0.1]
m4/stable 1.4.18-3 i686 [upgradable from: 1.4.18-1]
ncurses/stable 6.1.20190928 i686 [upgradable from: 6.1.20190511-7]
ndk-sysroot/stable 20-6 i686 [upgradable from: 20-1]
openssh/stable 8.1p1 i686 [upgradable from: 8.0p1-4]
openssl/stable 1.1.1d-1 i686 [upgradable from: 1.1.1c-2]
strace/stable 5.3 i686 [upgradable from: 5.2]
termux-tools/stable 0.72 all [upgradable from: 0.69-2]
texinfo/stable 6.7 i686 [upgradable from: 6.6-1]
Subscribed repositories:
https://dl.bintray.com/grimler/science-packages-24 science/stable
https://dl.bintray.com/grimler/game-packages-24 games/stable
https://dl.bintray.com/termux/termux-packages-24 stable/main
System information:
Linux localhost 3.18.0-19747-gd0dcdfafc1b5 #1 SMP PREEMPT Mon Oct 21 01:01:50 PDT 2019 i686 Android
Termux-packages arch:
i686
Android version:
9
Device manufacturer:
Google
Device model:
Samsung Chromebook Pro