Welcome Screen accessibility improvements

Change-Id: I2fa2f98566378a5f9ad12e3c74cbe293d97eb2a4
Reviewed-by: Kai Koehne <kai.koehne@digia.com>
Reviewed-by: Eike Ziller <eike.ziller@digia.com>

share/qtcreator/welcomescreen/widgets/LinkedText.qml

@@ -105,4 +105,5 @@ NativeText {
             }
         ]
     }
+    Accessible.role: Accessible.Link
 }

share/qtcreator/welcomescreen/widgets/NativeText.qml

@@ -31,4 +31,6 @@ import QtQuick 2.1
 
 Text {
     renderType: Text.NativeRendering
+    Accessible.name: text
+    Accessible.role: Accessible.StaticText
 }

share/qtcreator/welcomescreen/widgets/SearchBar.qml

@@ -59,4 +59,7 @@ Rectangle {
             }
         }
     }
+    Accessible.name: text
+    Accessible.description: placeholderText
+    Accessible.role: Accessible.EditableText
 }