compile error: duplicating Structure instance, use unowned variable or explicitly invoke copy method

[Pim Vullers]

When trying to compile audience from trunk I get the following error:

/tmp/portage/media-video/audience-9999/work/audience-9999/Audience/Widgets/VideoPlayer.vala:327.67-327.75: error: duplicating Structure instance, use unowned variable or explicitly invoke copy method
                el.post_message (new Gst.Message.application (el, structure));
                                                                  ^^^^^^^^^

** (valac-0.22:23023): CRITICAL **: vala_ccode_function_call_add_argument: assertion `expr != NULL' failed
/tmp/portage/media-video/audience-9999/work/audience-9999/Audience/Widgets/VideoPlayer.vala:332.67-332.75: error: duplicating Structure instance, use unowned variable or explicitly invoke copy method
                el.post_message (new Gst.Message.application (el, structure));
                                                                  ^^^^^^^^^

** (valac-0.22:23023): CRITICAL **: vala_ccode_function_call_add_argument: assertion `expr != NULL' failed
Compilation failed: 2 error(s), 117 warning(s)
make[2]: *** [Audience/Audience.c] Error 1
make[2]: Leaving directory `/tmp/portage/media-video/audience-9999/work/audience-9999_build'
make[1]: *** [CMakeFiles/audience.dir/all] Error 2
make[1]: Leaving directory `/tmp/portage/media-video/audience-9999/work/audience-9999_build'
make: *** [all] Error 2

This is with vala 0.22.0

[Pim Vullers (pimvullers)]

The attached patch solves the problem for me. Please verify and apply to trunk.