Android: Remove native views when their window is destroyd.

destroySurface() was not removing the native view as they are not
in the m_surfaces map.

Task-number: QTBUG-40159
Change-Id: Ib5457e0bd34141654fa47883f5e125d894b0bd05
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@digia.com>

src/plugins/platforms/android/androidjnimain.cpp

@@ -413,10 +413,9 @@ namespace QtAndroid
     {
         QMutexLocker lock(&m_surfacesMutex);
         const auto &it = m_surfaces.find(surfaceId);
-        if (it == m_surfaces.end())
-            return;
+        if (it != m_surfaces.end())
+            m_surfaces.remove(surfaceId);
 
-        m_surfaces.remove(surfaceId);
         QJNIEnvironmentPrivate env;
         if (!env)
             return;