Move precompilation-related flags to flags list.

runtime/vm/weak_code.cc

Index: runtime/vm/weak_code.cc
diff --git a/runtime/vm/weak_code.cc b/runtime/vm/weak_code.cc
index 0c5cca214ea661a16c4831fb461829bd51cc11e6..eb04d1f339b30ec3f57e39c0621e15ea632d28ee 100644
--- a/runtime/vm/weak_code.cc
+++ b/runtime/vm/weak_code.cc
@@ -13,8 +13,6 @@
 
 namespace dart {
 
-DECLARE_FLAG(bool, precompilation);
-
 bool WeakCodeReferences::HasCodes() const {
   return !array_.IsNull() && (array_.Length() > 0);
 }
@@ -68,7 +66,7 @@ void WeakCodeReferences::DisableCode() {
   if (code_objects.IsNull()) {
     return;
   }
-  ASSERT(!FLAG_precompilation);
+  ASSERT(!FLAG_precompiled_mode);
   UpdateArrayTo(Object::null_array());
   // Disable all code on stack.
   Code& code = Code::Handle();