Fix crash when Android Style is set more than once.

Load again JSON document is it was freed.

Task-number: QTBUG-43111
Change-Id: I22f1de221371b49fec8b3d66ad5f0bd2af9656fe
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@theqtcompany.com>

src/plugins/platforms/android/qandroidplatformintegration.cpp

@@ -79,8 +79,11 @@ void *QAndroidPlatformNativeInterface::nativeResourceForIntegration(const QByteA
     if (resource == "QtActivity")
         return QtAndroid::activity();
     if (resource == "AndroidStyleData") {
-        if (m_androidStyle)
+        if (m_androidStyle) {
+            if (m_androidStyle->m_styleData.isEmpty())
+                m_androidStyle->m_styleData = AndroidStyle::loadStyleData();
             return &m_androidStyle->m_styleData;
+        }
         else
             return Q_NULLPTR;
     }

src/plugins/platforms/android/qandroidplatformtheme.cpp

@@ -176,7 +176,7 @@ static void setPaletteColor(const QVariantMap &object,
     }
 }
 
-static std::shared_ptr<AndroidStyle> loadAndroidStyle(QPalette *defaultPalette)
+QJsonObject AndroidStyle::loadStyleData()
 {
     QString stylePath(QLatin1String(qgetenv("MINISTRO_ANDROID_STYLE_PATH")));
     const QLatin1Char slashChar('/');
@@ -198,21 +198,29 @@ static std::shared_ptr<AndroidStyle> loadAndroidStyle(QPalette *defaultPalette)
 
     QFile f(stylePath + QLatin1String("style.json"));
     if (!f.open(QIODevice::ReadOnly))
-        return std::shared_ptr<AndroidStyle>();
+        return QJsonObject();
 
     QJsonParseError error;
     QJsonDocument document = QJsonDocument::fromJson(f.readAll(), &error);
     if (document.isNull()) {
         qCritical() << error.errorString();
-        return std::shared_ptr<AndroidStyle>();
+        return QJsonObject();
     }
 
     if (!document.isObject()) {
         qCritical() << "Style.json does not contain a valid style.";
-        return std::shared_ptr<AndroidStyle>();
+        return QJsonObject();
     }
+    return document.object();
+}
+
+static std::shared_ptr<AndroidStyle> loadAndroidStyle(QPalette *defaultPalette)
+{
     std::shared_ptr<AndroidStyle> style(new AndroidStyle);
-    style->m_styleData = document.object();
+    style->m_styleData = AndroidStyle::loadStyleData();
+    if (style->m_styleData.isEmpty())
+        return std::shared_ptr<AndroidStyle>();
+
     for (QJsonObject::const_iterator objectIterator = style->m_styleData.constBegin();
          objectIterator != style->m_styleData.constEnd();
          ++objectIterator) {

src/plugins/platforms/android/qandroidplatformtheme.h

@@ -46,12 +46,12 @@ QT_BEGIN_NAMESPACE
 
 struct AndroidStyle
 {
+    static QJsonObject loadStyleData();
     QJsonObject m_styleData;
     QPalette m_standardPalette;
     QHash<int, QPalette> m_palettes;
     QHash<int, QFont> m_fonts;
     QHash<QByteArray, QFont> m_QWidgetsFonts;
-    QHash<QByteArray, QFont> m_QWidgetsPalettes;
 };
 
 class QAndroidPlatformNativeInterface;