Handle ACTION_POINTER_UP with tablet events

The ACTION_POINTER_UP is used when a non-primary pointer (touch, mouse
stylus, eraser) goes up. Without handling this action in these
cases, the table event remains in 'down' state (misses the
QEvent::TabletRelease) and as a consequence when it is next put on the
screen, eg. a line will be drawn to the new position (in case of a drawing
application).

In addition use getActionMasked() to get the action; non-masked
events would contain the index of the pointer too, and wouldn't
match with ACTION_POINTER_UP whose numeric value is 6. Rather the
actions would be in the lines of:
261, // ACTION_POINTER_DOWN(1), 6 with getActionMasked()
517, // ACTION_POINTER_DOWN(2), 6 with getActionMasked()
And so on.

Pick-to: 6.6 6.5
Fixes: QTBUG-86297
Change-Id: I1b50ca4d19b611aec8a5c280ed0521e2f11797b0
Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>
Reviewed-by: Assam Boudjelthia <assam.boudjelthia@qt.io>

src/android/jar/src/org/qtproject/qt/android/QtNative.java

@@ -581,7 +581,7 @@ public class QtNative
         if (event.getToolType(0) == MotionEvent.TOOL_TYPE_MOUSE) {
             sendMouseEvent(event, id);
         } else if (m_tabletEventSupported && pointerType != 0) {
-            tabletEvent(id, event.getDeviceId(), event.getEventTime(), event.getAction(), pointerType,
+            tabletEvent(id, event.getDeviceId(), event.getEventTime(), event.getActionMasked(), pointerType,
                 event.getButtonState(), event.getX(), event.getY(), event.getPressure());
         } else {
             touchBegin(id);

src/plugins/platforms/android/androidjniinput.cpp

@@ -312,6 +312,7 @@ namespace QtAndroidInput
         Qt::MouseButtons buttons = Qt::NoButton;
         switch (action) {
         case 1:     // ACTION_UP
+        case 6:     // ACTION_POINTER_UP, happens if stylus is not the primary pointer
         case 212:   // stylus release while side-button held on Galaxy Note 4
             buttons = Qt::NoButton;
             break;