Implement basic support for input method events.

This is needed to get text input working again on Mac.
Underlines are currently being ignored.

Change-Id: I2a1074a1151e9be6f96ebe12fd0bb40a0eb63d6a
Reviewed-by: Zeno Albisser <zeno.albisser@digia.com>

src/core/render_widget_host_view_qt.cpp

@@ -62,6 +62,7 @@
 #include <QEvent>
 #include <QFocusEvent>
 #include <QGuiApplication>
+#include <QInputMethodEvent>
 #include <QKeyEvent>
 #include <QMouseEvent>
 #include <QScreen>
@@ -703,6 +704,9 @@ bool RenderWidgetHostViewQt::forwardEvent(QEvent *event)
     case QEvent::FocusOut:
         handleFocusEvent(static_cast<QFocusEvent*>(event));
         break;
+    case QEvent::InputMethod:
+        handleInputMethodEvent(static_cast<QInputMethodEvent*>(event));
+        break;
     default:
         return false;
     }
@@ -850,6 +854,22 @@ void RenderWidgetHostViewQt::handleKeyEvent(QKeyEvent *ev)
     m_host->ForwardKeyboardEvent(WebEventFactory::toWebKeyboardEvent(ev));
 }
 
+void RenderWidgetHostViewQt::handleInputMethodEvent(QInputMethodEvent *ev)
+{
+    if (!m_host)
+        return;
+
+    if (ev->commitString().length())
+        m_host->ImeConfirmComposition(toString16(ev->commitString()), gfx::Range::InvalidRange(), false);
+
+    if (ev->preeditString().length()) {
+        // FIXME: Implement translation from QInputMethodEvent::Attribute list to WebKit::WebCompositionUnderlines.
+        std::vector<WebKit::WebCompositionUnderline> underlines;
+        int start = ev->replacementStart();
+        m_host->ImeSetComposition(toString16(ev->preeditString()), underlines, start, start + ev->replacementLength());
+    }
+}
+
 void RenderWidgetHostViewQt::handleWheelEvent(QWheelEvent *ev)
 {
     m_host->ForwardWheelEvent(WebEventFactory::toWebWheelEvent(ev, dpiScale()));

src/core/render_widget_host_view_qt.h

@@ -180,6 +180,7 @@ public:
     void handleTouchEvent(QTouchEvent*);
     void handleHoverEvent(QHoverEvent*);
     void handleFocusEvent(QFocusEvent*);
+    void handleInputMethodEvent(QInputMethodEvent*);
 
 #if defined(OS_MACOSX)
     virtual void SetTakesFocusOnlyOnMouseDown(bool flag) Q_DECL_OVERRIDE { QT_NOT_YET_IMPLEMENTED }

src/core/render_widget_host_view_qt_delegate.h

@@ -55,6 +55,7 @@ class QQuickWindow;
 class QSGNode;
 class QVariant;
 class QWindow;
+class QInputMethodEvent;
 QT_END_NAMESPACE
 
 class WebContentsAdapterClient;

src/webengine/render_widget_host_view_qt_delegate_quick.h

@@ -202,6 +202,11 @@ public:
         return m_client->inputMethodQuery(query);
     }
 
+    virtual void inputMethodEvent(QInputMethodEvent *event) Q_DECL_OVERRIDE
+    {
+        m_client->forwardEvent(event);
+    }
+
 protected:
     void geometryChanged(const QRectF &newGeometry, const QRectF &oldGeometry)
     {