Disable long press on Android

Remove the mapping from press-and-hold to right-mouse-button
press. This logic was implemented in the android plugin, and
there was no way to disable it for applications that needed
to handle long presses in a different way.

Add an environment variable to enable the mapping for those
who really need it, but do not advertise it. (We want to
add a proper API for this in 5.2)

Task-number: QTBUG-31644

Change-Id: Ia5ae75d6147485b73c78b7c3fa88d11af5d84c06
Reviewed-by: BogDan Vatra <bogdan@kde.org>

src/plugins/platforms/android/src/androidjniinput.cpp

@@ -163,6 +163,10 @@ namespace QtAndroidInput
 
     static void longPress(JNIEnv */*env*/, jobject /*thiz*/, jint /*winId*/, jint x, jint y)
     {
+        //### TODO: add proper API for Qt 5.2
+        static bool rightMouseFromLongPress = qgetenv("QT_NECESSITAS_COMPATIBILITY_LONG_PRESS").toInt();
+        if (!rightMouseFromLongPress)
+            return;
         m_ignoreMouseEvents = true;
         QPoint globalPos(x,y);
         QWindow *tlw = topLevelWindowAt(globalPos);