Remove more feature in product mode

runtime/vm/flow_graph_allocator.cc

Index: runtime/vm/flow_graph_allocator.cc
diff --git a/runtime/vm/flow_graph_allocator.cc b/runtime/vm/flow_graph_allocator.cc
index e83221259457c9d6c9d91e6c8c3aad3841405c72..b9bb33c2fc2617752c35f8c7e6d016568edeec91 100644
--- a/runtime/vm/flow_graph_allocator.cc
+++ b/runtime/vm/flow_graph_allocator.cc
@@ -2969,8 +2969,12 @@ void FlowGraphAllocator::AllocateRegisters() {
 
     THR_Print("-- [before ssa allocator] ir [%s] -------------\n",
               function.ToFullyQualifiedCString());
-    FlowGraphPrinter printer(flow_graph_, true);
-    printer.PrintBlocks();
+    if (FLAG_support_il_printer) {
+#ifndef PRODUCT
+      FlowGraphPrinter printer(flow_graph_, true);
+      printer.PrintBlocks();
+#endif
+    }
     THR_Print("----------------------------------------------\n");
   }
 
@@ -3010,8 +3014,12 @@ void FlowGraphAllocator::AllocateRegisters() {
 
     THR_Print("-- [after ssa allocator] ir [%s] -------------\n",
               function.ToFullyQualifiedCString());
-    FlowGraphPrinter printer(flow_graph_, true);
-    printer.PrintBlocks();
+    if (FLAG_support_il_printer) {
+#ifndef PRODUCT
+      FlowGraphPrinter printer(flow_graph_, true);
+      printer.PrintBlocks();
+#endif
+    }
     THR_Print("----------------------------------------------\n");
   }
 }