This fixes issue 667.
In the case where the frame was an odd number of pixels
wide or high, the border was being extended by one col
or row too far.
The calculation of color plane dimensions was modified
to use those already computed at the time the frame
buffer was allocated.
Also freed the temporary scaling buffer in vpxdec to
prevent a memory leak.
Change-Id: I195bc81d84c0fc5d8260c1232200d62399e4b51f
2e88f2f2ec