Property type conflicts with major versions

Pre-condition: the same type exists in different major versions:

• qtquickcontrols1/plugin.cpp:

  qmlRegisterType<QQuickExclusiveGroup>("QtQuick.Controls", 1, 0, "ExclusiveGroup");
  

• qtquickcontrols2plugin.cpp:

  qmlRegisterType<QQuickExclusiveGroup>("QtQuick.Controls", 2, 0, "ExclusiveGroup");
  

Consider the following variations to import the two modules:

• A

  import QtQuick.Controls 1.4
  import QtQuick.Controls 2.0
  

• B

  import QtQuick.Controls 2.0
  import QtQuick.Controls 1.4
  

• C

  import QtQuick.Controls 1.4
  import QtQuick.Controls 2.0 as C2
  

• D

  import QtQuick.Controls 2.0 as C2
  import QtQuick.Controls 1.4
  

• E

  import QtQuick.Controls 2.0
  import QtQuick.Controls 1.4 as C1
  

• F

  import QtQuick.Controls 1.4 as C1
  import QtQuick.Controls 2.0
  

Test snippets:

• 1

  ApplicationWindow {
      visible: true
      // all ok :)
      ExclusiveGroup { }
  }
  

• 2

  ApplicationWindow {
      visible: true
      ExclusiveGroup { id: grp }
      // C,E: ok
      // A,B,D,F: Unable to assign QQuickExclusiveGroup to QQuickExclusiveGroup
      property ExclusiveGroup eg: grp
  

• 3

  ApplicationWindow {
      visible: true
      // A,B,D,F: ok
      // C,E: Cannot assign object to property
      property ExclusiveGroup eg: ExclusiveGroup { }
  }