Image statusChanged signal is emited twice

The statusChanged signal is emited twice when the image is already in cache.

A patch that solves this problem is attached.

Code to reproduce the bug:

Item {
id: root
width: 600
height: 600

Image {
anchors.fill: parent
fillMode: Image.PreserveAspectFit
onStatusChanged: console.log("satus changed: " + status)

MouseArea

{ anchors.fill: parent onPressed: parent.source = "http://fc06.deviantart.net/fs14/f/2007/033/6/e/Dwarf_vs_Orc_by_GENZOMAN.jpg"; onReleased: parent.source = "http://th03.deviantart.net/fs71/PRE/f/2009/361/5/c/Orc_Warlock_by_kerembeyit.jpg"; }

}
}

How to reproduce:

1. Click and wait for the first image to be loaded
2. Release and wait for the second image to be loaded
3. Click again