Track the 'awaiter return' call stack use it to detect uncaught exceptions in async functions

runtime/vm/raw_object.h

 // 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.
 
 #ifndef RUNTIME_VM_RAW_OBJECT_H_
 #define RUNTIME_VM_RAW_OBJECT_H_
 
 #include "platform/assert.h"
 #include "vm/atomic.h"
 #include "vm/globals.h"
@@ skipping 1123 matching lines @@
   RawInstructions* instructions_;  // Accessed from generated code.
   // If owner_ is Function::null() the owner is a regular stub.
   // If owner_ is a Class the owner is the allocation stub for that class.
   // Else, owner_ is a regular Dart Function.
   RawObject* owner_;  // Function, Null, or a Class.
   RawExceptionHandlers* exception_handlers_;
   RawPcDescriptors* pc_descriptors_;
   RawArray* stackmaps_;
   RawArray* inlined_id_to_function_;
   RawCodeSourceMap* code_source_map_;
+  NOT_IN_PRECOMPILED(RawArray* await_token_positions_);
   NOT_IN_PRECOMPILED(RawInstructions* active_instructions_);
   NOT_IN_PRECOMPILED(RawArray* deopt_info_array_);
   // (code-offset, function, code) triples.
   NOT_IN_PRECOMPILED(RawArray* static_calls_target_table_);
   // If return_address_metadata_ is a Smi, it is the offset to the prologue.
   // Else, return_address_metadata_ is null.
   NOT_IN_PRECOMPILED(RawObject* return_address_metadata_);
   NOT_IN_PRECOMPILED(RawLocalVarDescriptors* var_descriptors_);
   NOT_IN_PRECOMPILED(RawArray* comments_);
   RawObject** to() {
@@ skipping 1283 matching lines @@
   COMPILE_ASSERT(kExternalTypedDataInt8ArrayCid ==
                  kTypedDataInt8ArrayViewCid + 15);
   COMPILE_ASSERT(kByteBufferCid == kExternalTypedDataInt8ArrayCid + 14);
   COMPILE_ASSERT(kNullCid == kByteBufferCid + 1);
   return (kNullCid - kTypedDataInt8ArrayCid);
 }
 
 }  // namespace dart
 
 #endif  // RUNTIME_VM_RAW_OBJECT_H_