docs(new): Adds TSDoc to Tracing class

new-docs/puppeteer.md

@@ -34,7 +34,7 @@
 |  [Target](./puppeteer.target.md) |  |
 |  [TimeoutError](./puppeteer.timeouterror.md) | TimeoutError is emitted whenever certain operations are terminated due to timeout. |
 |  [Touchscreen](./puppeteer.touchscreen.md) | The Touchscreen class exposes touchscreen events. |
-|  [Tracing](./puppeteer.tracing.md) |  |
+|  [Tracing](./puppeteer.tracing.md) | The Tracing class exposes the tracing audit interface. |
 |  [WebWorker](./puppeteer.webworker.md) | The WebWorker class represents a [WebWorker](https://developer.mozilla.org/en-US/docs/Web/API/Web_Workers_API)<!-- -->. |
 
 ## Enumerations

new-docs/puppeteer.tracing.md

@@ -4,17 +4,29 @@
 
 ## Tracing class
 
+The Tracing class exposes the tracing audit interface.
+
 <b>Signature:</b>
 
 ```typescript
 export declare class Tracing 
 ```
 
-## Constructors
+## Remarks
 
-|  Constructor | Modifiers | Description |
-|  --- | --- | --- |
-|  [(constructor)(client)](./puppeteer.tracing._constructor_.md) |  | Constructs a new instance of the <code>Tracing</code> class |
+You can use `tracing.start` and `tracing.stop` to create a trace file which can be opened in Chrome DevTools or [timeline viewer](https://chromedevtools.github.io/timeline-viewer/)<!-- -->.
+
+The constructor for this class is marked as internal. Third-party code should not call the constructor directly or create subclasses that extend the `Tracing` class.
+
+## Example
+
+
+```js
+await page.tracing.start({path: 'trace.json'});
+await page.goto('https://www.google.com');
+await page.tracing.stop();
+
+```
 
 ## Properties
 
@@ -28,6 +40,6 @@ export declare class Tracing
 
 |  Method | Modifiers | Description |
 |  --- | --- | --- |
-|  [start(options)](./puppeteer.tracing.start.md) |  |  |
-|  [stop()](./puppeteer.tracing.stop.md) |  |  |
+|  [start(options)](./puppeteer.tracing.start.md) |  | Starts a trace for the current page. |
+|  [stop()](./puppeteer.tracing.stop.md) |  | Stops a trace started with the <code>start</code> method. |
 

new-docs/puppeteer.tracing.start.md

@@ -4,6 +4,8 @@
 
 ## Tracing.start() method
 
+Starts a trace for the current page.
+
 <b>Signature:</b>
 
 ```typescript
@@ -14,9 +16,13 @@ start(options?: TracingOptions): Promise<void>;
 
 |  Parameter | Type | Description |
 |  --- | --- | --- |
-|  options | TracingOptions |  |
+|  options | TracingOptions | Optional <code>TracingOptions</code>. |
 
 <b>Returns:</b>
 
 Promise&lt;void&gt;
 
+## Remarks
+
+Only one trace can be active at a time per browser.
+

new-docs/puppeteer.tracing.stop.md

@@ -4,6 +4,8 @@
 
 ## Tracing.stop() method
 
+Stops a trace started with the `start` method.
+
 <b>Signature:</b>
 
 ```typescript
@@ -13,3 +15,5 @@ stop(): Promise<Buffer>;
 
 Promise&lt;Buffer&gt;
 
+Promise which resolves to buffer with trace data.
+

src/common/Tracing.ts

@@ -23,15 +23,37 @@ interface TracingOptions {
   categories?: string[];
 }
 
+/**
+ * The Tracing class exposes the tracing audit interface.
+ * @remarks
+ * You can use `tracing.start` and `tracing.stop` to create a trace file
+ * which can be opened in Chrome DevTools or {@link https://chromedevtools.github.io/timeline-viewer/ | timeline viewer}.
+ *
+ * @example
+ * ```js
+ * await page.tracing.start({path: 'trace.json'});
+ * await page.goto('https://www.google.com');
+ * await page.tracing.stop();
+ * ```
+ */
 export class Tracing {
   _client: CDPSession;
   _recording = false;
   _path = '';
 
+  /**
+   * @internal
+   */
   constructor(client: CDPSession) {
     this._client = client;
   }
 
+  /**
+   * Starts a trace for the current page.
+   * @remarks
+   * Only one trace can be active at a time per browser.
+   * @param options - Optional `TracingOptions`.
+   */
   async start(options: TracingOptions = {}): Promise<void> {
     assert(
       !this._recording,
@@ -68,6 +90,10 @@ export class Tracing {
     });
   }
 
+  /**
+   * Stops a trace started with the `start` method.
+   * @returns Promise which resolves to buffer with trace data.
+   */
   async stop(): Promise<Buffer> {
     let fulfill: (value: Buffer) => void;
     const contentPromise = new Promise<Buffer>((x) => (fulfill = x));