The offset from fp to the register file is based on the frame size
-- which is one slot larger when embedded constant pools are enabled.

TEST=unittests/DecodeBytecodeAndOperands
R=rmcilroy@chromium.org, bmeurer@chromium.org, oth@chromium.org, mstarzinger@chromium.org
BUG=

Review URL: https://codereview.chromium.org/1906963002

Cr-Commit-Position: refs/heads/master@{#35735}