Crash fix when loading NPAPI plugins on Qt/Mac
Crash fix when loading NPAPI plugins on Qt/Mac

Reviewed by Ariya Hidayat.

There's no guarantee that the plist will be valid even if we
ask the plugin to create it. Crash obverved with iGetter.

* plugins/mac/PluginPackageMac.cpp:

git-svn-id: bf5cd6ccde378db821296732a091cfbcf5285fbd@49677 bbb929c8-8fbe-4397-9dbb-9b2b20218538
primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs,primiano/blink-gitcs