Fix breakage with app hosting beta API switch (#7896)

* Fix breakage with app hosting beta API switch

* Changelog

Author: inlined

CHANGELOG.md

@@ -1 +1,2 @@
+- Fixes an error creating a rollout with App Hosting in the beta API (#7896)
 - Added support for Next.js 15. (#7588)

src/apphosting/backend.spec.ts

@@ -136,12 +136,6 @@ describe("apphosting setup functions", () => {
       expect(updateTrafficStub).to.be.calledWith(projectId, location, backendId, {
         rolloutPolicy: {
           codebaseBranch: "main",
-          stages: [
-            {
-              progression: "IMMEDIATE",
-              targetPercent: 100,
-            },
-          ],
         },
       });
     });

src/apphosting/backend.ts

@@ -361,12 +361,6 @@ export async function setDefaultTrafficPolicy(
   const traffic: DeepOmit<apphosting.Traffic, apphosting.TrafficOutputOnlyFields | "name"> = {
     rolloutPolicy: {
       codebaseBranch: codebaseBranch,
-      stages: [
-        {
-          progression: "IMMEDIATE",
-          targetPercent: 100,
-        },
-      ],
     },
   };
   const op = await apphosting.updateTraffic(projectId, location, backendId, traffic);

src/gcp/apphosting.ts

@@ -139,7 +139,6 @@ export interface Rollout {
   pauseTime: string;
   error?: Error;
   build: string;
-  stages?: RolloutStage[];
   displayName?: string;
   createTime: string;
   updateTime: string;
@@ -193,9 +192,7 @@ export type TrafficOutputOnlyFields =
   | "updateTime"
   | "etag"
   | "uid"
-  | "rolloutPolicy.disabledTime"
-  | "rolloutPolicy.stages.startTime"
-  | "rolloutPolicy.stages.endTime";
+  | "rolloutPolicy.disabledTime";
 
 assertImplements<TrafficOutputOnlyFields, RecursiveKeyOf<Traffic>>();
 
@@ -213,7 +210,6 @@ export interface RolloutPolicy {
   codebaseBranch?: string;
   codebaseTagPattern?: string;
   // end oneof trigger
-  stages?: RolloutStage[];
   disabled?: boolean;
 
   // TODO: This will be undefined if disabled is not true, right?