Enable causal stacktrace in kernel

runtime/vm/kernel_reader.cc

 // Copyright (c) 2016, 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/kernel_reader.h"
 
 #include <string.h>
 
 #include "vm/dart_api_impl.h"
 #include "vm/longjump.h"
@@ skipping 418 matching lines @@
   function.set_kernel_function(kernel_procedure);
 
   function.set_is_debuggable(
       kernel_procedure->function()->dart_async_marker() == FunctionNode::kSync);
   switch (kernel_procedure->function()->dart_async_marker()) {
     case FunctionNode::kSyncStar:
       function.set_modifier(RawFunction::kSyncGen);
       break;
     case FunctionNode::kAsync:
       function.set_modifier(RawFunction::kAsync);
+      function.set_is_inlinable(!FLAG_causal_async_stacks);
       break;
     case FunctionNode::kAsyncStar:
       function.set_modifier(RawFunction::kAsyncGen);
+      function.set_is_inlinable(!FLAG_causal_async_stacks);
       break;
     default:
       // no special modifier
       break;
   }
   ASSERT(kernel_procedure->function()->async_marker() == FunctionNode::kSync);
 
   if (native_name != NULL) {
     function.set_native_name(*native_name);
   }
@@ skipping 364 matching lines @@
   initializer_fun.set_is_debuggable(false);
   initializer_fun.set_is_reflectable(false);
   initializer_fun.set_is_inlinable(false);
   return new (zone) ParsedFunction(thread, initializer_fun);
 }
 
 
 }  // namespace kernel
 }  // namespace dart
 #endif  // !defined(DART_PRECOMPILED_RUNTIME)