windeployqt: Fall back comparing names of QML modules when their class name is empty

QtWebEngine and some other modules have empty class names, so they are
dropped when concatenating QML imports.

Task-number: QTBUG-61957
Change-Id: I06ccf8ab54b2d3ffba04f15746722f5b3596d5d9
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>

src/windeployqt/qmlutils.cpp

@@ -39,6 +39,11 @@
 
 QT_BEGIN_NAMESPACE
 
+bool operator==(const QmlImportScanResult::Module &m1, const QmlImportScanResult::Module &m2)
+{
+    return m1.className.isEmpty() ? m1.name == m2.name : m1.className == m2.className;
+}
+
 // Return install path (cp -r semantics)
 QString QmlImportScanResult::Module::installPath(const QString &root) const
 {
@@ -153,19 +158,10 @@ QmlImportScanResult runQmlImportScanner(const QString &directory, const QString
     return result;
 }
 
-static inline bool contains(const QList<QmlImportScanResult::Module> &modules, const QString &className)
-{
-    for (const QmlImportScanResult::Module &m : modules) {
-        if (m.className == className)
-            return true;
-    }
-    return false;
-}
-
 void QmlImportScanResult::append(const QmlImportScanResult &other)
 {
     for (const QmlImportScanResult::Module &module : other.modules) {
-        if (!contains(modules, module.className))
+        if (std::find(modules.cbegin(), modules.cend(), module) == modules.cend())
             modules.append(module);
     }
     for (const QString &plugin : other.plugins) {

src/windeployqt/qmlutils.h

@@ -55,6 +55,8 @@ struct QmlImportScanResult {
     QStringList plugins;
 };
 
+bool operator==(const QmlImportScanResult::Module &m1, const QmlImportScanResult::Module &m2);
+
 QmlImportScanResult runQmlImportScanner(const QString &directory, const QString &qmlImportPath,
                                         bool usesWidgets, int platform, DebugMatchMode debugMatchMode,
                                         QString *errorMessage);