Don't use a special var descriptor for :async_op since it can now be either stack or context alloca…

runtime/vm/compiler.cc

 // Copyright (c) 2012, 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/compiler.h"
 
 #include "vm/assembler.h"
 
 #include "vm/ast_printer.h"
 #include "vm/block_scheduler.h"
@@ skipping 909 matching lines @@
     const int8_t kind = var_info.kind();
     if (kind == RawLocalVarDescriptors::kSavedCurrentContext) {
       THR_Print("  saved current CTX reg offset %d\n", var_info.index());
     } else {
       if (kind == RawLocalVarDescriptors::kContextLevel) {
         THR_Print("  context level %d scope %d", var_info.index(),
             var_info.scope_id);
       } else if (kind == RawLocalVarDescriptors::kStackVar) {
         THR_Print("  stack var '%s' offset %d",
           var_name.ToCString(), var_info.index());
-      } else if (kind == RawLocalVarDescriptors::kContextVar) {
+      } else {
+        ASSERT(kind == RawLocalVarDescriptors::kContextVar);
         THR_Print("  context var '%s' level %d offset %d",
             var_name.ToCString(), var_info.scope_id, var_info.index());
-      } else {
-        ASSERT(kind == RawLocalVarDescriptors::kAsyncOperation);
-        THR_Print("  async operation '%s' level %d offset %d",
-            var_name.ToCString(), var_info.scope_id, var_info.index());
       }
       THR_Print(" (valid %d-%d)\n", var_info.begin_pos, var_info.end_pos);
     }
   }
   THR_Print("}\n");
 
   THR_Print("Exception Handlers for function '%s' {\n", function_fullname);
   const ExceptionHandlers& handlers =
         ExceptionHandlers::Handle(code.exception_handlers());
   THR_Print("%s}\n", handlers.ToCString());
@@ skipping 473 matching lines @@
     const Object& result =
       PassiveObject::Handle(isolate->object_store()->sticky_error());
     isolate->object_store()->clear_sticky_error();
     return result.raw();
   }
   UNREACHABLE();
   return Object::null();
 }
 
 }  // namespace dart