cherry-pick(#15152): chore: undeprecate sync headers()

docs/src/api/class-request.md

@@ -59,7 +59,9 @@ Returns the [Frame] that initiated this request.
 ## method: Request.headers
 - returns: <[Object]<[string], [string]>>
 
-**DEPRECATED** Incomplete list of headers as seen by the rendering engine. Use [`method: Request.allHeaders`] instead.
+An object with the request HTTP headers. The header names are lower-cased.
+Note that this method does not return security-related headers, including cookie-related ones.
+You can use [`method: Request.allHeaders`] for complete list of headers that include `cookie` information.
 
 ## async method: Request.headersArray
 - returns: <[Array]<[Object]>>

docs/src/api/class-response.md

@@ -30,7 +30,9 @@ Indicates whether this Response was fullfilled by a Service Worker's Fetch Handl
 ## method: Response.headers
 - returns: <[Object]<[string], [string]>>
 
-**DEPRECATED** Incomplete list of headers as seen by the rendering engine. Use [`method: Response.allHeaders`] instead.
+An object with the response HTTP headers. The header names are lower-cased.
+Note that this method does not return security-related headers, including cookie-related ones.
+You can use [`method: Response.allHeaders`] for complete list of headers that include `cookie` information.
 
 ## async method: Response.headersArray
 - returns: <[Array]<[Object]>>

packages/playwright-core/types/types.d.ts

@@ -14858,9 +14858,10 @@ export interface Request {
   frame(): Frame;
 
   /**
-   * **DEPRECATED** Incomplete list of headers as seen by the rendering engine. Use
+   * An object with the request HTTP headers. The header names are lower-cased. Note that this method does not return
-   * [request.allHeaders()](https://playwright.dev/docs/api/class-request#request-all-headers) instead.
+   * security-related headers, including cookie-related ones. You can use
-   * @deprecated
+   * [request.allHeaders()](https://playwright.dev/docs/api/class-request#request-all-headers) for complete list of headers
+   * that include `cookie` information.
    */
   headers(): { [key: string]: string; };
 
@@ -15095,9 +15096,10 @@ export interface Response {
   fromServiceWorker(): boolean;
 
   /**
-   * **DEPRECATED** Incomplete list of headers as seen by the rendering engine. Use
+   * An object with the response HTTP headers. The header names are lower-cased. Note that this method does not return
-   * [response.allHeaders()](https://playwright.dev/docs/api/class-response#response-all-headers) instead.
+   * security-related headers, including cookie-related ones. You can use
-   * @deprecated
+   * [response.allHeaders()](https://playwright.dev/docs/api/class-response#response-all-headers) for complete list of
+   * headers that include `cookie` information.
    */
   headers(): { [key: string]: string; };