[ACS4.4] cherry pick commit 4e44ac56c92221c5b9509dca18e14befd7e297fe

[Sanjay Tripathi]

Hi Hugo/Daan,

Could you please cherry-pick following commit to 4.4 branch.

Commit: 4e44ac56c92221c5b9509dca18e14befd7e297fe

CLOUDSTACK=6678: API:MS: listCapacity returns; 
errorcode":530,"cserrorcode":9999,"errortext":"Index: 0, Size: 0"}.

--Sanjay