input: Add the Shift-modifier

Part-of: <https://gitlab.gnome.org/World/Phosh/squeekboard/-/merge_requests/696>

src/action.rs

@@ -15,6 +15,7 @@ pub enum Modifier {
     /// Control and Alt are the only modifiers
     /// which doesn't interfere with levels,
     /// so it's simple to implement as levels are deprecated in squeekboard.
+    Shift,
     Control,
     Alt,
     Mod4,

src/data/parsing.rs

@@ -420,6 +420,9 @@ fn create_action<H: logging::Handler>(
             }).collect(),
         },
         SubmitData::Modifier(modifier) => match modifier {
+            Modifier::Shift => action::Action::ApplyModifier(
+                action::Modifier::Shift,
+            ),
             Modifier::Control => action::Action::ApplyModifier(
                 action::Modifier::Control,
             ),

src/submission.rs

@@ -238,6 +238,7 @@ impl Submission {
     fn update_modifiers(&mut self) {
         let raw_modifiers = self.modifiers_active.iter()
             .map(|(_id, m)| match m {
+                Modifier::Shift => Modifiers::SHIFT,
                 Modifier::Control => Modifiers::CONTROL,
                 Modifier::Alt => Modifiers::MOD1,
                 Modifier::Mod4 => Modifiers::MOD4,