[debug] add exception predictions to builtins where missing.

src/builtins/builtins-promise.cc

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/builtins/builtins-promise.h"
 #include "src/builtins/builtins-constructor.h"
 #include "src/builtins/builtins-utils.h"
 #include "src/builtins/builtins.h"
 #include "src/code-factory.h"
 #include "src/code-stub-assembler.h"
@@ skipping 728 matching lines @@
         Label reject(this);
         Node* const has_handler = PromiseHasHandler(result);
 
         // Promise has already been rejected, but had no handler.
         // Revoke previously triggered reject event.
         GotoIf(has_handler, &reject);
         CallRuntime(Runtime::kPromiseRevokeReject, context, result);
         Goto(&reject);
 
         Bind(&reject);
-        // Don't cause a debug event as this case is forwarding a rejection
+        // Don't cause a debug event as this case is forwarding a rejection.
         InternalPromiseReject(context, promise, thenable_value, false);
         PromiseSetHasHandler(result);
         Goto(&out);
       }
     }
   }
 
   Bind(&if_notnativepromise);
   {
     // 8. Let then be Get(resolution, "then").
@@ skipping 62 matching lines @@
         CallRuntime(Runtime::kNewTypeError, context, message_id, result);
     var_reason.Bind(error);
 
     // 6.b Return RejectPromise(promise, selfResolutionError).
     Goto(&if_rejectpromise);
   }
 
   // 9.a Return RejectPromise(promise, then.[[Value]]).
   Bind(&if_rejectpromise);
   {
-    InternalPromiseReject(context, promise, var_reason.value(), true);
+    // Don't cause a debug event as this case is forwarding a rejection.
+    InternalPromiseReject(context, promise, var_reason.value(), false);

[Yang, 2017/03/06 11:45:02]

In the test case we break twice, once in the getter where we throw the
exception, and a second time in Promise.resolve itself, where we trigger a
PromiseReject event. The PromiseReject event is redundant.

     Goto(&out);
   }
 
   Bind(&out);
 }
 
 void PromiseBuiltinsAssembler::PromiseFulfill(
     Node* context, Node* promise, Node* result,
     v8::Promise::PromiseState status) {
   Label do_promisereset(this), debug_async_event_enqueue_recurring(this);
@@ skipping 930 matching lines @@
     // 5. Return ?  Invoke(promise, "then", « thenFinally, catchFinally »).
     Node* const result =
         CallJS(call_callable, context, then, promise, var_then_finally.value(),
                var_catch_finally.value());
     Return(result);
   }
 }
 
 }  // namespace internal
 }  // namespace v8