Fixed handling of QInputMethodEvents with nonzero replacementLength.

These types of events replace text that is already in the widget, but
WebKit did not check for replacementLength at all.

RevBy:    Janne Koskinen
Task:     QT-4303
Task:     https://bugs.webkit.org/show_bug.cgi?id=49787
AutoTest: Included

Author: axis

src/3rdparty/webkit/WebKit/qt/Api/qwebpage.cpp

@@ -1257,9 +1257,15 @@ void QWebPagePrivate::inputMethodEvent(QInputMethodEvent *ev)
         }
     }
 
-    if (!ev->commitString().isEmpty())
+    if (renderTextControl && ev->replacementLength() > 0) {
+        renderTextControl->setSelectionStart(qMax(renderTextControl->selectionStart() + ev->replacementStart(), 0));
+        renderTextControl->setSelectionEnd(qMin(renderTextControl->selectionStart() + ev->replacementLength(), static_cast<int>(renderTextControl->text().length())));
+        // Commit regardless of whether commitString is empty, to get rid of selection.
         editor->confirmComposition(ev->commitString());
-    else if (!ev->preeditString().isEmpty()) {
+    } else if (!ev->commitString().isEmpty()) {
+        editor->confirmComposition(ev->commitString());
+    }
+    if (!ev->preeditString().isEmpty()) {
         QString preedit = ev->preeditString();
         editor->setComposition(preedit, underlines, preedit.length(), 0);
     }

src/3rdparty/webkit/WebKit/qt/tests/qwebpage/tst_qwebpage.cpp

@@ -1494,6 +1494,20 @@ void tst_QWebPage::inputMethods()
     QCOMPARE(value, QString("QtWebKit"));
 #endif
 
+    {
+        QList<QInputMethodEvent::Attribute> attributes;
+        QInputMethodEvent event(QString(), attributes);
+        event.setCommitString("XXX", 0, 0);
+        page->event(&event);
+        event.setCommitString(QString(), -2, 2); // Erase two characters.
+        page->event(&event);
+        event.setCommitString(QString(), -1, 1); // Erase one character.
+        page->event(&event);
+        variant = page->inputMethodQuery(Qt::ImSurroundingText);
+        value = variant.value<QString>();
+        QCOMPARE(value, QString("QtWebKit"));
+    }
+
     //ImhHiddenText
     QMouseEvent evpresPassword(QEvent::MouseButtonPress, inputs.at(1).geometry().center(), Qt::LeftButton, Qt::NoButton, Qt::NoModifier);
     page->event(&evpresPassword);