[turbofan] Ship generators if --turbo-from-bytecode set.

src/ast/ast-numbering.cc

Index: src/ast/ast-numbering.cc
diff --git a/src/ast/ast-numbering.cc b/src/ast/ast-numbering.cc
index 6de950161867257d0006407550fab84c35e6849a..e1b11f655a844f2f92f9557db9c85bd7215a8e4d 100644
--- a/src/ast/ast-numbering.cc
+++ b/src/ast/ast-numbering.cc
@@ -592,10 +592,12 @@ bool AstNumberingVisitor::Renumber(FunctionLiteral* node) {
   }
 
   if (IsGeneratorFunction(node->kind()) || IsAsyncFunction(node->kind())) {
-    // TODO(neis): We may want to allow Turbofan optimization here if
-    // --turbo-from-bytecode is set and we know that Ignition is used.
-    // Unfortunately we can't express that here.
-    DisableOptimization(kGenerator);
+    // Generators can be optimized if --turbo-from-bytecode is set.
+    if (FLAG_turbo_from_bytecode) {
+      DisableCrankshaft(kGenerator);
+    } else {
+      DisableOptimization(kGenerator);
+    }
   }
 
   VisitDeclarations(scope->declarations());