Initialize dummy variables.
Initialize dummy variables.

Valgrind flags these up as needed by handle_inter_mode.
Initializing fixes some assertion failures in the unit tests with
only ref-mv enabled.

Change-Id: I4d56c356692745dbecd9f790cdbb8dbfbaf72d55

smarter/aom,mbebenita/aom,mbebenita/aom,luctrudeau/aom,smarter/aom,luctrudeau/aom,mbebenita/aom,mbebenita/aom,mbebenita/aom,smarter/aom,luctrudeau/aom,GrokImageCompression/aom,smarter/aom,mbebenita/aom,luctrudeau/aom,GrokImageCompression/aom,smarter/aom,GrokImageCompression/aom,mbebenita/aom,luctrudeau/aom,GrokImageCompression/aom,smarter/aom,luctrudeau/aom,GrokImageCompression/aom,mbebenita/aom,mbebenita/aom,GrokImageCompression/aom