Android/LinuxFb: fix QWidget::showFullScreen()

Previously, showFullScreen() had a race condition: it depended
on QFbScreen::setGeometry() being called after the window state was
set (that would trigger QPlatformScreen::resizeMaximizedWindows(), which
was the only part of the code that reacted to WindowFullScreen).
On Android this caused random behaviour.

Task-number: QTBUG-33294
Change-Id: I228e6af4139af1a47387e7d80757d7b46e859580
Reviewed-by: Jørgen Lind <jorgen.lind@digia.com>
Reviewed-by: Laszlo Agocs <laszlo.agocs@digia.com>

src/platformsupport/fbconvenience/qfbwindow.cpp

@@ -77,6 +77,26 @@ void QFbWindow::setGeometry(const QRect &rect)
     QPlatformWindow::setGeometry(rect);
 }
 
+void QFbWindow::setVisible(bool visible)
+{
+    if (visible) {
+        if (mWindowState & Qt::WindowFullScreen)
+            setGeometry(platformScreen()->geometry());
+        else if (mWindowState & Qt::WindowMaximized)
+            setGeometry(platformScreen()->availableGeometry());
+    }
+    QPlatformWindow::setVisible(visible);
+}
+
+
+void QFbWindow::setWindowState(Qt::WindowState state)
+{
+    QPlatformWindow::setWindowState(state);
+    mWindowState = state;
+    platformScreen()->invalidateRectCache();
+}
+
+
 void QFbWindow::setWindowFlags(Qt::WindowFlags flags)
 {
     mWindowFlags = flags;

src/platformsupport/fbconvenience/qfbwindow_p.h

@@ -59,7 +59,9 @@ public:
     virtual void lower();
 
     virtual void setGeometry(const QRect &rect);
+    virtual void setVisible(bool visible);
 
+    virtual void setWindowState(Qt::WindowState state);
     virtual void setWindowFlags(Qt::WindowFlags type);
     virtual Qt::WindowFlags windowFlags() const;
 
@@ -78,6 +80,7 @@ protected:
     QFbBackingStore *mBackingStore;
     QRect mOldGeometry;
     Qt::WindowFlags mWindowFlags;
+    Qt::WindowState mWindowState;
 
     WId mWindowId;
 };