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

Source/devtools/protocol.json

Index: Source/devtools/protocol.json
diff --git a/Source/devtools/protocol.json b/Source/devtools/protocol.json
index 9531b6f9286ef21257bc92d004c904a65cda9a2b..7428e366ef37729da433d91af7107aad05731d8f 100644
--- a/Source/devtools/protocol.json
+++ b/Source/devtools/protocol.json
@@ -3522,7 +3522,7 @@
                 "name": "paused",
                 "parameters": [
                     { "name": "callFrames", "type": "array", "items": { "$ref": "CallFrame" }, "description": "Call stack the virtual machine stopped on." },
-                    { "name": "reason", "type": "string", "enum": [ "XHR", "DOM", "EventListener", "exception", "assert", "CSPViolation", "debugCommand", "other" ], "description": "Pause reason." },
+                    { "name": "reason", "type": "string", "enum": [ "XHR", "DOM", "EventListener", "exception", "assert", "CSPViolation", "debugCommand", "promiseRejection", "other" ], "description": "Pause reason." },
                     { "name": "data", "type": "object", "optional": true, "description": "Object containing break-specific auxiliary properties." },
                     { "name": "hitBreakpoints", "type": "array", "optional": true, "items": { "type": "string" }, "description": "Hit breakpoints IDs", "hidden": true },
                     { "name": "asyncStackTrace", "$ref": "StackTrace", "optional": true, "description": "Async stack trace, if any.", "hidden": true }