Reapply "DWARF and unwind support for AOT assembly output."

runtime/vm/dart.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/dart.h"
 
 #include "vm/become.h"
 #include "vm/clustered_snapshot.h"
 #include "vm/code_observers.h"
 #include "vm/cpu.h"
@@ skipping 689 matching lines @@
 #else
     buffer.AddString(" x64-sysv");
 #endif
 #elif defined(TARGET_ARCH_DBC)
     buffer.AddString(" dbc");
 #elif defined(TARGET_ARCH_DBC64)
     buffer.AddString(" dbc64");
 #endif
   }
 
+  if (FLAG_dwarf_stack_traces) {
+    buffer.AddString(" dwarf-stack-traces");
+  }
+
   return buffer.Steal();
 }
 
 
 void Dart::RunShutdownCallback() {
   Isolate* isolate = Isolate::Current();
   void* callback_data = isolate->init_callback_data();
   Dart_IsolateShutdownCallback callback = Isolate::ShutdownCallback();
   if (callback != NULL) {
     (callback)(callback_data);
@@ skipping 44 matching lines @@
   return predefined_handles_->handles_.IsValidScopedHandle(address);
 }
 
 
 bool Dart::IsReadOnlyApiHandle(Dart_Handle handle) {
   ASSERT(predefined_handles_ != NULL);
   return predefined_handles_->api_handles_.IsValidHandle(handle);
 }
 
 }  // namespace dart