Revert "Improved 1-pass CBR rate control"

This reverts commit b5ea2fbc2c1554769848774c836aad262af95072. Further
testing showed noticable keyframe popping in some cases, reverting this
for now to give time for a proper fix.

Conflicts:

	vp8/encoder/onyx_if.c
	vp8/encoder/ratectrl.c

Change-Id: I159f53d1bf0e24c035754ab3ded8ccfd58fd04af
5 files changed