wasm-split fails on small module with existing unused table

[kripken]

(module
 (table $0 10 10 funcref)

 (export "hashMemory" (func $1))

 (func $0 (result i32)
  (unreachable)
 )
 (func $1 (result i32)
  (unreachable)
 )
)

$ bin/wasm-split w.wat --split --split-funcs 1 --primary-output a.wasm.primary.wasm --secondary-output a.wasm.secondary.wasm -all
wasm-split: wasm-binary.cpp:686: uint32_t wasm::WasmBinaryWriter::getTableIndex(wasm::Name) const: Assertion `it != indexes.tableIndexes.end()' failed.
Aborted

cc @tlively