Expose the item as well as the source component for the BreezeBlock

This way we can access the items, it can be needed to extract data
from them

lookandfeel/contents/components/BreezeBlock.qml

@@ -25,8 +25,10 @@ import QtQuick.Controls 1.1
 import org.kde.plasma.core 2.0 as PlasmaCore
 
 Item {
-    property alias mainItem: view.sourceComponent
+    property alias main: view.sourceComponent
     property alias controls: controlsLayout.sourceComponent
+    readonly property alias mainItem: view.item
+    readonly property alias controlsItem: controlsLayout.item
 
     property bool canShutdown: false
     property bool canReboot: false

lookandfeel/contents/components/LogoutScreen.qml

@@ -56,7 +56,7 @@ BreezeBlock {
         onTriggered: remainingTime--
     }
 
-    mainItem: ColumnLayout {
+    main: ColumnLayout {
         spacing: 0
         BreezeHeading {
             id: actionLabel

lookandfeel/contents/lockscreen/LockScreen.qml

@@ -62,7 +62,7 @@ Image {
         }
 
         initialItem: BreezeBlock {
-            mainItem: UserSelect {
+            main: UserSelect {
                 id: usersSelection
                 model: ListModel {
                     id: users