Add APIs to surface VMState and new EmbedderState to CpuProfile samples.

EmbedderState:
* An EmbedderState is defined as a value uint8_t and a v8::context used
for filtering.
* EmbedderStates are stack allocated by the embedder, construction and
destruction set/unset the state to the isolate thread local top.
* A v8::context is used to filter states that are added to a CpuProfile,
if the CpuProfile do not have a ContextFilter set or if contexts do not
match, state defaults to Empty.

* v8:StateTag is already propagated all the way to a Sample, simply add
an API to surface it.

VMState: 
Change-Id: I7eed08907360b99b0ad20ddcff59c95c7076c85e
Bug: chromium:1263871
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3188072
Auto-Submit: Corentin Pescheloche <cpescheloche@fb.com>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78250}