1.26.0

• new lint: combinators_ordering
• fixed use_colored_box and use_decorated_box to not over-report
  on containers without a child
• fixed false positive for unnecessary_parenthesis on a map-or-set
  literal at the start of an expression statement
• fixed false positive for prefer_final_locals reporting on fields
• fixed unnecessary_overrides to allow overrides on @Protected
  members
• fixed unnecessary_parenthesis false positives on map and set
  literal at the beginning of expressions
• fixed avoid_multiple_declarations_per_line false positive in
  for statements
• fixed prefer_final_locals false positive on declaration lists
  with at least one non-final variable
• fixed use_build_context_synchronously to handle awaits in
  if conditions

/cc @srawlins @bwilkerson @a14n