Create WebView using Activity context

Create WebView using the Activity context instead of the Application
context. This ensures that the WebView is tied to the life of the
Activity and not the Application.

Test: manual testing
Test: CTS test
Bug: 256047823
Change-Id: Ib3aff49ab0fb297194394d11a16937369afcc6a0

packages/CarrierDefaultApp/src/com/android/carrierdefaultapp/SliceStoreActivity.java

@@ -85,7 +85,7 @@ public class SliceStoreActivity extends Activity {
 
         SliceStoreBroadcastReceiver.updateSliceStoreActivity(mCapability, this);
 
-        mWebView = new WebView(getApplicationContext());
+        mWebView = new WebView(this);
         setContentView(mWebView);
         mWebView.loadUrl(mUrl.toString());
         // TODO(b/245882601): Get back response from WebView