Adds support for loading from and storing to outer context
variables. Also adds support for declaring functions on contexts and
locals. Finally, fixes a couple of issues with StaContextSlot where
we weren't emitting the write barrier and therefore would crash in the
GC.

Also added code so that --print-bytecode will output the
function name before the bytecodes, and replaces MachineType with StoreRepresentation in RawMachineAssembler::Store and updates tests.

BUG=v8:4280
LOG=N

Review URL: https://codereview.chromium.org/1425633002

Cr-Commit-Position: refs/heads/master@{#31584}