Make the clipboard paste from the outside work correctly

During the previous refactoring, two exceptions that triggered
native copy/paste events were omitted.

Fixes: QTBUG-106668
Change-Id: Ie61dd6a0c1d9d2fdd47bd94be055d0221feae25b
Reviewed-by: Lorn Potter <lorn.potter@gmail.com>
(cherry picked from commit 38049164c370dd424afe0c4574b458f7bd79083b)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
Reviewed-by: Morten Johan Sørvig <morten.sorvig@qt.io>

src/plugins/platforms/wasm/qwasmclipboard.cpp

@@ -284,19 +284,21 @@ void QWasmClipboard::setMimeData(QMimeData *mimeData, QClipboard::Mode mode)
     isPaste = false;
 }
 
-bool QWasmClipboard::processKeyboard(const QWasmEventTranslator::TranslatedEvent &event,
+QWasmClipboard::ProcessKeyboardResult
+QWasmClipboard::processKeyboard(const QWasmEventTranslator::TranslatedEvent &event,
                                 const QFlags<Qt::KeyboardModifier> &modifiers)
 {
-    // Clipboard path: cut/copy/paste are handled by clipboard event or direct clipboard
+    if (event.type != QEvent::KeyPress || !modifiers.testFlag(Qt::ControlModifier))
-    // access.
+        return ProcessKeyboardResult::Ignored;
-    if (hasClipboardApi)
+
-        return false;
+    if (event.key != Qt::Key_C && event.key != Qt::Key_V && event.key != Qt::Key_X)
-    if (event.type != QEvent::KeyPress || !modifiers.testFlag(Qt::ControlModifier)
+        return ProcessKeyboardResult::Ignored;
-        || (event.key != Qt::Key_C && event.key != Qt::Key_V && event.key != Qt::Key_X)) {
+
-        return false;
-    }
     isPaste = event.key == Qt::Key_V;
-    return true;
+
+    return hasClipboardApi && !isPaste
+            ? ProcessKeyboardResult::NativeClipboardEventAndCopiedDataNeeded
+            : ProcessKeyboardResult::NativeClipboardEventNeeded;
 }
 
 bool QWasmClipboard::supportsMode(QClipboard::Mode mode) const

src/plugins/platforms/wasm/qwasmclipboard.h

@@ -19,6 +19,12 @@ QT_BEGIN_NAMESPACE
 class QWasmClipboard : public QObject, public QPlatformClipboard
 {
 public:
+    enum class ProcessKeyboardResult {
+        Ignored,
+        NativeClipboardEventNeeded,
+        NativeClipboardEventAndCopiedDataNeeded,
+    };
+
     QWasmClipboard();
     virtual ~QWasmClipboard();
 
@@ -29,7 +35,7 @@ public:
     bool ownsMode(QClipboard::Mode mode) const override;
 
     static void qWasmClipboardPaste(QMimeData *mData);
-    bool processKeyboard(const QWasmEventTranslator::TranslatedEvent &event,
+    ProcessKeyboardResult processKeyboard(const QWasmEventTranslator::TranslatedEvent &event,
                                           const QFlags<Qt::KeyboardModifier> &modifiers);
     void initClipboardPermissions();
     void installEventHandlers(const emscripten::val &canvas);

src/plugins/platforms/wasm/qwasmcompositor.cpp

@@ -1146,21 +1146,30 @@ void QWasmCompositor::WindowManipulation::onPointerUp(const PointerEvent& event)
 
 bool QWasmCompositor::processKeyboard(int eventType, const EmscriptenKeyboardEvent *emKeyEvent)
 {
+    constexpr bool ProceedToNativeEvent = false;
     Q_ASSERT(eventType == EMSCRIPTEN_EVENT_KEYDOWN || eventType == EMSCRIPTEN_EVENT_KEYUP);
 
     auto translatedEvent = m_eventTranslator->translateKeyEvent(eventType, emKeyEvent);
 
     const QFlags<Qt::KeyboardModifier> modifiers = KeyboardModifier::getForEvent(*emKeyEvent);
 
-    if (QWasmIntegration::get()->getWasmClipboard()->processKeyboard(translatedEvent, modifiers))
+    const auto clipboardResult = QWasmIntegration::get()->getWasmClipboard()->processKeyboard(
-        return false;
+            translatedEvent, modifiers);
+
+    using ProcessKeyboardResult = QWasmClipboard::ProcessKeyboardResult;
+    if (clipboardResult == ProcessKeyboardResult::NativeClipboardEventNeeded)
+        return ProceedToNativeEvent;
 
     if (translatedEvent.text.isEmpty())
         translatedEvent.text = QString(emKeyEvent->key);
     if (translatedEvent.text.size() > 1)
         translatedEvent.text.clear();
-    return QWindowSystemInterface::handleKeyEvent<QWindowSystemInterface::SynchronousDelivery>(
+    const auto result =
+            QWindowSystemInterface::handleKeyEvent<QWindowSystemInterface::SynchronousDelivery>(
                     0, translatedEvent.type, translatedEvent.key, modifiers, translatedEvent.text);
+    return clipboardResult == ProcessKeyboardResult::NativeClipboardEventAndCopiedDataNeeded
+            ? ProceedToNativeEvent
+            : result;
 }
 
 bool QWasmCompositor::processWheel(int eventType, const EmscriptenWheelEvent *wheelEvent)