keyboard: Switch back from shift to default level on more situations

If the shift key was pressed, we should switch back to the default level
after the next commit. It seems that this only worked due to a superfluous
signal emission so far (see https://gitlab.gnome.org/GNOME/mutter/-/issues/3448).

When the keyboard is in this "shift" level (note: only "shift", not
"opt+shift" level) without being latched, there are certain events that
should put it back into the default level:

- A normal character key on the OSK being pressed
- A keyval on the extended OSK (eg. TAB key or an arrow key) being pressed
- The backspace key being pressed
- The OSK being hidden
- The user moving focus in the entry

The `_updateLevelFromHints()` function already takes care of updating the
active level after certain kinds of events, we can achieve the desired
behavior by adding a fallback case to that function where it moves the level
back from "shift" to "default".

Since we only want this switch back to the "default" layer as a response to
actual user input, add a `userInputHappened` boolean to
`_updateLevelFromHints()` and don't set that when the application simply
changes its content hints.

Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/3286>

js/ui/keyboard.js

@@ -1243,7 +1243,7 @@ export const Keyboard = GObject.registerClass({
     _onFocusPositionChanged(focusTracker) {
         let rect = focusTracker.getCurrentRect();
         this.setCursorLocation(focusTracker.currentWindow, rect.x, rect.y, rect.width, rect.height);
-        this._updateLevelFromHints();
+        this._updateLevelFromHints(true);
     }
 
     _onDestroy() {
@@ -1320,10 +1320,10 @@ export const Keyboard = GObject.registerClass({
 
     _onContentHintsChanged(controller, contentHint) {
         this._contentHint = contentHint;
-        this._updateLevelFromHints();
+        this._updateLevelFromHints(false);
     }
 
-    _updateLevelFromHints() {
+    _updateLevelFromHints(userInputHappened) {
         // If the latch is enabled, avoid level changes
         if (this._latched)
             return;
@@ -1338,10 +1338,15 @@ export const Keyboard = GObject.registerClass({
 
         if ((this._contentHint & Clutter.InputContentHintFlags.UPPERCASE) !== 0) {
             this._setActiveLevel('shift');
-        } else if (!this._surroundingTextId &&
-                   (this._contentHint &
-                    (Clutter.InputContentHintFlags.AUTO_CAPITALIZATION |
-                     Clutter.InputContentHintFlags.TITLECASE)) !== 0) {
+            return;
+        }
+
+        if ((this._contentHint &
+             (Clutter.InputContentHintFlags.AUTO_CAPITALIZATION |
+              Clutter.InputContentHintFlags.TITLECASE)) !== 0) {
+            if (this._surroundingTextId)
+                return;
+
             this._surroundingTextId =
                 Main.inputMethod.connect('surrounding-text-set', () => {
                     const [text, cursor] = Main.inputMethod.getSurroundingText();
@@ -1369,7 +1374,11 @@ export const Keyboard = GObject.registerClass({
                     this._surroundingTextId = 0;
                 });
             Main.inputMethod.request_surrounding();
+            return;
         }
+
+        if (userInputHappened && this._currentPage === this._layers['shift'])
+            this._setActiveLevel('default');
     }
 
     _onKeyFocusChanged() {
@@ -1495,6 +1504,7 @@ export const Keyboard = GObject.registerClass({
                 button.connect('released', () => {
                     if (key.action === 'hide') {
                         this.close(true);
+                        this._updateLevelFromHints(true);
                     } else if (key.action === 'languageMenu') {
                         this._popupLanguageMenu(button);
                     } else if (key.action === 'emoji') {
@@ -1504,6 +1514,7 @@ export const Keyboard = GObject.registerClass({
                     } else if (key.action === 'delete') {
                         this._keyboardController.toggleDelete(true);
                         this._keyboardController.toggleDelete(false);
+                        this._updateLevelFromHints(true);
                     } else if (!this._longPressed && key.action === 'levelSwitch') {
                         this._setActiveLevel(key.level);
                         this._setLatched(
@@ -1517,18 +1528,13 @@ export const Keyboard = GObject.registerClass({
                 button.connect('keyval', (_actor, keyval) => {
                     this._keyboardController.keyvalPress(keyval);
                     this._keyboardController.keyvalRelease(keyval);
+                    this._updateLevelFromHints(true);
                 });
             } else {
                 button.connect('commit', (_actor, str) => {
                     this._keyboardController.commit(str, this._modifiers).then(() => {
                         this._disableAllModifiers();
-                        if (layout.mode === 'default' ||
-                            (layout.mode === 'latched' && !this._latched)) {
-                            if (this._contentHint !== 0)
-                                this._updateLevelFromHints();
-                            else
-                                this._setActiveLevel('default');
-                        }
+                        this._updateLevelFromHints(true);
                     }).catch(console.error);
                 });
             }