Add doc (13279)

Signed-off-by: Nester.zhou <ester.zhou@huawei.com>

en/release-notes/changelogs/OpenHarmony_3.2.8.1/changelogs-testfwk_arkxtest.md

+# Test Subsystem ChangeLog
+
+## cl.testfwk_arkxtest.1 Exception Handling Support of On, Driver, and Component APIs
+
+The original APIs in API version 8 are deprecated, and substitute APIs that support exception handling are introduced in API version 9. You must use **try catch** to capture exceptions thrown by the APIs.
+
+## Change Impacts
+
+This change affects the JS APIs in API version 9 provided by **@ohos.uitest**. If you have used the API of **@ohos.uitest-api9** during test case development, adaptation is required so that the compilation can be successful in the SDK environment of the new version.
+
+## Key API/Component Changes
+
+- The **By** class in API version 8 is deprecated and replaced by the **On** class in API version 9. The APIs of the **On** class support exception handling and retain their original name, with the exception of **By#key**, which is renamed **On.id**.
+- The **BY** object in API version 8 is deprecated and replaced by the **ON** object in API version 9.
+- The **UiDriver** class in API version 8 is deprecated and replaced by the **Driver** class in API version 9. The APIs of the **Driver** class support exception handling and retain their original name.
+- The **UiComponent** class in API version 8 is deprecated and replaced by the **Component** class in API version 9. The APIs of the **Component** class support exception handling and retain their original name.
+
+## Adaptation Guide
+
+1. Adapt to the API name changes.
+
+   You can replace the class name according to the following rules:
+
+   - `By-->On`
+   - `BY-->ON`
+   - `UiDriver-->Driver`
+   - `UiComponent-->Component`
+
+2. Catch and handle exceptions.
+
+   Use **try-catch** to catch and handle exceptions thrown by the APIs. Below is the sample code:
+
+   ```typescript
+   import {Driver,ON,Component} from '@ohos.uitest'
+   
+   try {
+       let driver = Driver.create();
+   } catch (error) {
+       // error handle; error.code indicates the error code.
+   }
+   ```
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