A small code clean on ext-inter
A small code clean on ext-inter

BUG=aomedia:442

Change-Id: I5cec560e427bf8628cbaae85aea4cdb19b74659f

GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom