Since the kernel vblocks are always padded out to a fixed size, the unused (padded) memory was ending up containing random bytes, leading to vbutil_kernel generating vblocks that are not bit-identical when run with the same inputs.
BUG=none
TEST=see below
1) Use vbutil_kernel with the same set of inputs to generate two alternative vblocks.
2) Compare the 2 files - they must be bitwise identical space. The padding bytes must all be set to 0.
3) Generate a new signed image using the resign_image.sh script under scripts/image_signing. This signed image should be boot and install successfully on a maching running our custom firmware using the same set of root, firmware, and kernel keys.
Review URL: http://codereview.chromium.org/3076033
Firmware-side code for LoadKernel() is in place now. LoadFirmware() replacement coming soon.
The new functions are implemented in parallel to the existing ones (i.e., everything that used to work still does).
Review URL: http://codereview.chromium.org/2745007
