[Tizen][Desktop] Show the minimize button in the titlebar

Newest implementations of Views are expecting an
implementation of the "CanMinimize()" function in the
delegate Window class ; otherwise, the "minimize" button
will not be shown in the titlebar.
ApplicationFileUtil: Stop leaking |prev_value|.

Stop allocating memory for a base::DictionaryValue() that is immediately
going to be overwritten, as the initial value then leaks.

CID=194508
CID=194777
BUG=XWALK-2928
Merge pull request #2611 from rakuco/CID-194508

ApplicationFileUtil: Stop leaking |prev_value|.
Merge pull request #2610 from Tarnyko/master

[Tizen][Desktop] Show the minimize button in the titlebar