Remove swap buffer speed feature

The inter prediction residual can undergo different transform types
during the rate-distortion optimization search. The assumption used
in this speed feature no longer holds true. This commit removes the
related code to clean up the codebase and clear out unit test
failure in higher speed setting.

Change-Id: I7f7cd4df2345ed3e607c9fae75b38cd2dbde0cac
3 files changed