Cleanup: No need to dynamically allocate a couple class members in mime_util_xdg.cc. Also convert a dynamically allocated class member to a scoper.
Cleanup: No need to dynamically allocate a couple class members in mime_util_xdg.cc. Also convert a dynamically allocated class member to a scoper.

BUG=none
TEST=none

Review URL: http://codereview.chromium.org/8372047

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@108197 0039d316-1c4b-4281-b951-d872f2087c98

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