In the calculations for aggregating size_delta_inserted and
size_delta_deleted, which aggregate the total binary additions and
deletions, there was a missing check for whether a file was binary or
not before adding the value. This caused a strange total binary change
to appear. This change adds the binary check and also updates tests
to accurately represent that non-binary changes can have size_delta as
an attribute.
Bug: Issue 4992
Change-Id: I52da1c8f9fdcf6be94658f1b95721453a71a4213
2e30833c4d