message: Update LegalizeTFControlFlow to not pass around module (NFC).
  tf.Case/tf.If/tf.While have been updated to use helper functions on the ops for accessing their associated functions, and module passed around have no uses.
diff: @@ -105,7 +105,7 @@ void ImportXlaRegion(mlir::FuncOp func, Region* dest_region, Location loc,
  }
  }
  -void LowerIf(TF::IfOp op, ModuleOp module) {
  +void LowerIf(TF::IfOp op) {
  Location loc = op.getLoc();
  OpBuilder builder(op);
  @@ -130,7 +130,7 @@ void LowerIf(TF::IfOp op, ModuleOp module) {
  op.erase();
  }
  -void LowerCase(TF::CaseOp op, ModuleOp module) {
  +void LowerCase(TF::CaseOp op) {
  Location loc = op.getLoc();
  OpBuilder builder(op);
  @@ -158,7 +158,7 @@ void LowerCase(TF::CaseOp op, ModuleOp module) {
  op.erase();
  }
  -void LowerWhile(TF::WhileOp op, ModuleOp module) {
  +void LowerWhile(TF::WhileOp op) {
  Location loc = op.getLoc();
  OpBuilder builder(op);
  @@ -301,11 +301,9 @@ void LowerWhileRegion(TF::WhileRegionOp op) {
  } // namespace
  void LegalizeTFControlFlow::runOnOperation() {
  - auto module = getOperation();
  -
  - module.walk([&](Operation* op) {
  + getOperation().walk([&](Operation* op) {
  if (auto while_op = dyn_cast<TF::WhileOp>(op)) {
  - LowerWhile(while_op, module);
  + LowerWhile(while_op);
  return;
  }
  if (auto while_region_op = dyn_cast<TF::WhileRegionOp>(op)) {
  @@ -313,11 +311,11 @@ void LegalizeTFControlFlow::runOnOperation() {
  return;
  }
  if (auto if_op = dyn_cast<TF::IfOp>(op)) {
  - LowerIf(if_op, module);
  + LowerIf(if_op);
  return;
  }
  if (auto case_op = dyn_cast<TF::CaseOp>(op)) {
  - LowerCase(case_op, module);
  + LowerCase(case_op);
  return;
  }
  });
  