vbv: use row wise IntraSatdCost to predict vbv intra frame bits.

If P/B slice is predominatly intra coded, use intra SatdCost to predict the row
bits in vbv.

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branch : stable
vbv: bug fixes - move row Predictors, frameSizeEstimated to Frame Encoder scope.

Improves quality and controls buffer underflow when Frame parallelism is enabled.

--HG--
branch : stable
rc: move qp2qscale and qscale2qp function to common

--HG--
branch : stable
vbv: bug fix - down shifting of satdcost for 10 bit depth.

--HG--
branch : stable