C++: Pass some values by reference

Change-Id: If2829e9ec5f796714bf3906c17c4c654cdfc4dea
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@digia.com>
ClassView: Optimize for loops

Change-Id: I429638e9eb3705a7ccf3c2a79bae1f0f58967893
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@digia.com>
Designer: Pass strings by reference

Change-Id: I86395393f5b79a2ade99e4422453bec5395d2898
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@digia.com>