(#3379 #3307) Fix accidentally consuming input events on alt key up (#3382)

## What's new?
- We were erroneously eating the event on complete, which made the final
"up" on an alt some times not complete 🤦

Author: RAOF

src/miral/minimal_window_manager.cpp

@@ -197,9 +197,8 @@ bool miral::MinimalWindowManager::handle_keyboard_event(MirKeyboardEvent const*
         switch (mir_keyboard_event_scan_code(event))
         {
             case KEY_LEFTALT:
-                if (self->application_selector.complete() != nullptr)
-                    return true;
-                break;
+                self->application_selector.complete();
+                [[fallthrough]];
             default:;
         }
     }

src/server/frontend_wayland/keyboard_helper.cpp

@@ -21,7 +21,6 @@
 #include "mir/events/keyboard_event.h"
 #include "mir/input/seat.h"
 #include "mir/fatal.h"
-#include "mir/log.h"
 
 #include <cstring> // memcpy
 #include <unordered_set>
@@ -62,7 +61,6 @@ void mf::KeyboardHelper::handle_event(std::shared_ptr<MirEvent const> const& eve
     switch (mir_input_event_get_type(mir_event_get_input_event(event.get())))
     {
     case mir_input_event_type_keyboard_resync:
-        mir::log_debug("mir_input_event_type_keyboard_resync is causing modifiers to be refreshed");
         refresh_modifiers();
         break;
 
@@ -150,20 +148,6 @@ void mf::KeyboardHelper::set_keymap(std::shared_ptr<mi::Keymap> const& new_keyma
 
 void mf::KeyboardHelper::set_modifiers(MirXkbModifiers const& new_modifiers)
 {
-    mir::log_debug(
-    "Modifiers are being set from: depressed=0x%08x, latched=0x%08x, locked=0x%08x, effective_layout=0x%08x",
-        modifiers.depressed,
-        modifiers.latched,
-        modifiers.locked,
-        modifiers.effective_layout);
-
-    mir::log_debug(
-        "Modifiers are being set to: depressed=0x%08x, latched=0x%08x, locked=0x%08x, effective_layout=0x%08x",
-        new_modifiers.depressed,
-        new_modifiers.latched,
-        new_modifiers.locked,
-        new_modifiers.effective_layout);
-
     if (new_modifiers != modifiers)
     {
         modifiers = new_modifiers;

src/server/frontend_wayland/wl_keyboard.cpp

@@ -83,8 +83,6 @@ void mf::WlKeyboard::focus_on(WlSurface* surface)
         auto const serial = client->next_serial(nullptr);
         send_enter_event(serial, surface->raw_resource(), &key_state);
         wl_array_release(&key_state);
-        mir::log_debug("Surface (id=%u) has been focused and is refreshing its modifiers",
-            wl_resource_get_id(surface->raw_resource()));
         helper->refresh_modifiers();
     }
 
@@ -112,13 +110,6 @@ void mf::WlKeyboard::send_key(std::shared_ptr<MirKeyboardEvent const> const& eve
 
 void mf::WlKeyboard::send_modifiers(MirXkbModifiers const& modifiers)
 {
-    mir::log_debug(
-        "Sending modifiers event: depressed=0x%08x, latched=0x%08x, locked=0x%08x, effective_layout=0x%08x",
-       modifiers.depressed,
-       modifiers.latched,
-       modifiers.locked,
-       modifiers.effective_layout);
-
     auto const serial = client->next_serial(nullptr);
     send_modifiers_event(
         serial,