Allows turning on checked mode on a per-isolate basis

runtime/vm/code_generator.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/code_generator.h"
 
 #include "vm/assembler.h"
 #include "vm/ast.h"
 #include "vm/code_patcher.h"
 #include "vm/compiler.h"
@@ skipping 209 matching lines @@
 DEFINE_RUNTIME_ENTRY(InstantiateTypeArguments, 2) {
   TypeArguments& type_arguments =
       TypeArguments::CheckedHandle(arguments.ArgAt(0));
   const TypeArguments& instantiator =
       TypeArguments::CheckedHandle(arguments.ArgAt(1));
   ASSERT(!type_arguments.IsNull() && !type_arguments.IsInstantiated());
   ASSERT(instantiator.IsNull() || instantiator.IsInstantiated());
   // Code inlined in the caller should have optimized the case where the
   // instantiator can be reused as type argument vector.
   ASSERT(instantiator.IsNull() || !type_arguments.IsUninstantiatedIdentity());
-  if (FLAG_enable_type_checks) {
+  if (Isolate::Current()->TypeChecksEnabled()) {
     Error& bound_error = Error::Handle();
     type_arguments =
         type_arguments.InstantiateAndCanonicalizeFrom(instantiator,
                                                       &bound_error);
     if (!bound_error.IsNull()) {
       // Throw a dynamic type error.
       const intptr_t location = GetCallerLocation();
       String& bound_error_message =  String::Handle(
           String::New(bound_error.ToErrorCString()));
       Exceptions::CreateAndThrowTypeError(
@@ skipping 284 matching lines @@
       // Note that instantiated_dst_type may be malbounded.
       dst_type_name = instantiated_dst_type.UserVisibleName();
       dst_type_lib =
           Class::Handle(instantiated_dst_type.type_class()).library();
     } else {
       dst_type_name = dst_type.UserVisibleName();
       dst_type_lib = Class::Handle(dst_type.type_class()).library();
     }
     String& bound_error_message =  String::Handle();
     if (!bound_error.IsNull()) {
-      ASSERT(FLAG_enable_type_checks);
+      ASSERT(Isolate::Current()->TypeChecksEnabled());
       bound_error_message = String::New(bound_error.ToErrorCString());
     }
     if (src_type_name.Equals(dst_type_name)) {
       // Qualify the names with their libraries.
       String& lib_name = String::Handle();
       lib_name = Library::Handle(
           Class::Handle(src_type.type_class()).library()).name();
       if (lib_name.Length() != 0) {
         lib_name = String::Concat(lib_name, Symbols::Dot());
         src_type_name = String::Concat(lib_name, src_type_name);
@@ skipping 1133 matching lines @@
   const intptr_t elm_size = old_data.ElementSizeInBytes();
   const TypedData& new_data =
       TypedData::Handle(TypedData::New(cid, new_size, Heap::kOld));
   TypedData::Copy(new_data, 0, old_data, 0, old_size * elm_size);
   typed_data_cell.SetAt(0, new_data);
   arguments.SetReturn(new_data);
 }
 
 
 }  // namespace dart