Revert "Trigger exception debug event for promises at the throw site."

test/mjsunit/es6/debug-promises-throw-in-constructor.js

-// Copyright 2014 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.
-
-// Flags: --harmony-promises --expose-debug-as debug
-
-// Test debug events when we only listen to uncaught exceptions and
-// an exception is thrown in the the Promise constructor.
-// We expect an Exception debug event with a promise to be triggered.
-
-Debug = debug.Debug;
-
-var step = 0;
-var exception = null;
-
-function listener(event, exec_state, event_data, data) {
-  try {
-    // Ignore exceptions during startup in stress runs.
-    if (step >= 1) return;
-    if (event == Debug.DebugEvent.Exception) {
-      assertEquals(0, step);
-      assertEquals("uncaught", event_data.exception().message);
-      assertTrue(event_data.promise() instanceof Promise);
-      assertTrue(event_data.uncaught());
-      // Assert that the debug event is triggered at the throw site.
-      assertTrue(exec_state.frame(0).sourceLineText().indexOf("// event") > 0);
-      step++;
-    }
-  } catch (e) {
-    // Signal a failure with exit code 1.  This is necessary since the
-    // debugger swallows exceptions and we expect the chained function
-    // and this listener to be executed after the main script is finished.
-    print("Unexpected exception: " + e + "\n" + e.stack);
-    exception = e;
-  }
-}
-
-Debug.setBreakOnUncaughtException();
-Debug.setListener(listener);
-
-var p = new Promise(function(resolve, reject) {
-  throw new Error("uncaught");  // event
-});
-
-assertEquals(1, step);
-assertNull(exception);