evas: Restore flag pre_render_done in render_mapped

evas: Restore flag pre_render_done in render_mapped

Some objects don't go through render_pre (unchanged, child
of mapped parents), even though they will go through
evas_render_mapped. Those were marked as pre_render_done
inside evas_render_mapped since it seemed to fix some issues
a long time ago.

Unfortunately, if those objects are changed their flag may
not be reset to false, which means they never go through
render_pre, leading to render issues.

I believe simply restoring the value of the pre_render_done
flag should be good enough. I don't know why it is set to
true inside evas_render_mapped but I also don't want to find
out :)

See 9ac13e4aec83ea6dadfa62e4253b1db4ffe167e8 (old)
See 87e5e70a9d888ce93ed807bb0d39d1738241ad9b (older)

Patch made with @jiin.moon