DevTools: Introduce Debugger::Reason::PromiseRejection pause reason.

LayoutTests/inspector/sources/debugger/debugger-pause-on-exception.html

Index: LayoutTests/inspector/sources/debugger/debugger-pause-on-exception.html
diff --git a/LayoutTests/inspector/sources/debugger/debugger-pause-on-exception.html b/LayoutTests/inspector/sources/debugger/debugger-pause-on-exception.html
index ad2967de325b8faef1c6b6276ee213454b3e0cf0..80c59b6583ba34d612843289186d4029337d6bc9 100644
--- a/LayoutTests/inspector/sources/debugger/debugger-pause-on-exception.html
+++ b/LayoutTests/inspector/sources/debugger/debugger-pause-on-exception.html
@@ -28,12 +28,12 @@ var test = function()
     {
         InspectorTest.addResult("Script source was shown.");
         InspectorTest.evaluateInPage("setTimeout(handleClick, 0)");
-        InspectorTest.waitUntilPaused(step3);
+        InspectorTest.waitUntilPausedAndDumpStackAndResume(step3);
     }
 
-    function step3(callFrames)
+    function step3()
     {
-        InspectorTest.captureStackTrace(callFrames);
+        DebuggerAgent.setPauseOnExceptions(WebInspector.DebuggerModel.PauseOnExceptionsState.DontPauseOnExceptions);
         InspectorTest.completeDebuggerTest();
     }
 }