GetMIMEDescription should return const char *

GetMIMEDescription should return const char *
https://bugs.webkit.org/show_bug.cgi?id=77297

Patch by John Yani <vanuan@gmail.com> on 2012-02-01
Reviewed by Alexey Proskuryakov.

No new tests. No change in behaviour.

* plugins/blackberry/PluginPackageBlackBerry.cpp:
(WebCore::PluginPackage::fetchInfo):
* plugins/efl/PluginPackageEfl.cpp:
(WebCore):
(WebCore::PluginPackage::fetchInfo):
* plugins/npapi.h:
* plugins/npfunctions.h:
* plugins/qt/PluginPackageQt.cpp:
(WebCore::PluginPackage::fetchInfo):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@106503 268f45cc-cd09-0410-ab3c-d52691b4dbfc