* master: (167 commits)
  stats: Avoid asserts in fuzz-tests by eliminating arbitrary length limits, using the new MemBlock wrapper for memcpy (envoyproxy#8779)
  Make %UPSTREAM_LOCAL_ADDRESS% access-log format work for HTTP requests. (envoyproxy#9362)
  tools: API boosting support for using decls and enum constants. (envoyproxy#9418)
  Fix incorrect cluster InitializePhase type (envoyproxy#9379)
  build: fix merge race between envoyproxy#9241 and envoyproxy#9413. (envoyproxy#9427)
  fuzz: fix incorrect evaluator test (envoyproxy#9402)
  server: fix bogus startup log message (envoyproxy#9404)
  tools: Add protoxform tests (envoyproxy#9241)
  api: options after import (envoyproxy#9413)
  misc: use std::move instead of constructing a copy (envoyproxy#9415)
  tools: API boosting support for rewriting elaborated types. (envoyproxy#9375)
  docs: fix invalid transport_socket value (envoyproxy#9403)
  fix typo in docs (envoyproxy#9394)
  srds: remove to-de-removed scopes first and then apply additions to avoid scope key conflict. (envoyproxy#9366)
  api: generate whole directory and sync (envoyproxy#9382)
  bazel: Add load statements for proto_library (envoyproxy#9367)
  Fix typo (envoyproxy#9388)
  Correct test of OptionsImpl argc type (Was: Correct type for std::array size() result) (envoyproxy#9290)
  http1 encode trailers in chunk encoding (envoyproxy#8667)
  Add mode to PipeInstance (envoyproxy#8423)
  ...

When Envoy splits the empty `--disable-extensions` flag at startup,
it ends up with a vector containing a single empty string. Since
the vector isn't empty, it tries to disable the extension with an
empty name. The fix is to not try to split the option string if it
is empty.

This fixes envoyproxy#9377.

Signed-off-by: James Peach <jpeach@apache.org>
Signed-off-by: Prakhar <prakhar_au@yahoo.com>