[M108 Aura Migration][NaCl][PPAPI]Fix PPAPI unittest error
This patch fixes below PPAPI unittest error:
[1] var_value_converter_unittest.cc build error
[2] MediaStreamBufferManager unittest execute error
error[1] was already fixed in patch:
[M108 Aura Migration][NaCl][PPFW] Enable VD Trusted Plugins functionality
https://review.tizen.org/gerrit/#/c/platform/framework/web/chromium-efl/+/289527/
Ported patch from tizen_7.0:
https://review.tizen.org/gerrit/#/c/270688/
Change-Id: Id837625846669d5622da9ae167ac7071a97ef5e8