Revert "Improvements to causal async stack traces"

runtime/vm/debugger.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_DEBUGGER_H_
 #define RUNTIME_VM_DEBUGGER_H_
 
 #include "include/dart_tools_api.h"
 
 #include "vm/object.h"
@@ skipping 331 matching lines @@
                                  intptr_t var_ctx_level);
 
   intptr_t TryIndex();
   void GetPcDescriptors();
   void GetVarDescriptors();
   void GetDescIndices();
 
   static const char* KindToCString(Kind kind) {
     switch (kind) {
       case kRegular:
-        return "Regular";
+        return "kRegular";
       case kAsyncCausal:
-        return "AsyncCausal";
+        return "kAsyncCausal";
       case kAsyncSuspensionMarker:
-        return "AsyncSuspensionMarker";
+        return "kAsyncSuspensionMarker";
       default:
         UNREACHABLE();
         return "";
     }
   }
 
   RawObject* GetStackVar(intptr_t slot_index);
   RawObject* GetContextVar(intptr_t ctxt_level, intptr_t slot_index);
 
   uword pc_;
@@ skipping 371 matching lines @@
 
   friend class Isolate;
   friend class BreakpointLocation;
   DISALLOW_COPY_AND_ASSIGN(Debugger);
 };
 
 
 }  // namespace dart
 
 #endif  // RUNTIME_VM_DEBUGGER_H_