These macros were previously defined in mozilla-config.h, but we're
not supposed to include those files according to the mozilla devs.
However, the macros must be defined for npapi.h to define the
necessary platform-specific structures.  This patch sets up the
macros before including npapi.h.
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>
(cherry picked from commit 877bd210)
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>