APK Build getting failed

## System info

Issue occurs on: Android
Plugin version: 0.3.11

## Steps to Reproduce
I'm using androidx in the project and when I try to build apk,,I'm not able to build apk due to some bug in flutter_webview plugin.

## Logs

`flutter analyze`
[ +2 ms] C:\src\flutter\.pub-cache\hosted\pub.dartlang.org\flutter_webview_plugin-0.3.11\android\src\main\java\com\flutter_webview_plugin\BrowserClient.java:80: warning:
[deprecation] shouldOverrideUrlLoading(WebView,String) in WebViewClient has been deprecated
[ +3 ms] public boolean shouldOverrideUrlLoading(WebView view, String url) {
[ ] ^
[ ] C:\src\flutter\.pub-cache\hosted\pub.dartlang.org\flutter_webview_plugin-0.3.11\android\src\main\java\com\flutter_webview_plugin\BrowserClient.java:103: warning:
[deprecation] onReceivedError(WebView,int,String,String) in WebViewClient has been deprecated
[ +28 ms] public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) {
[ +1 ms] ^
[ +3 ms] C:\src\flutter\.pub-cache\hosted\pub.dartlang.org\flutter_webview_plugin-0.3.11\android\src\main\java\com\flutter_webview_plugin\BrowserClient.java:104: warning:
[deprecation] onReceivedError(WebView,int,String,String) in WebViewClient has been deprecated
[ +2 ms] super.onReceivedError(view, errorCode, description, failingUrl);
[ ] ^
[ ] C:\src\flutter\.pub-cache\hosted\pub.dartlang.org\flutter_webview_plugin-0.3.11\android\src\main\java\com\flutter_webview_plugin\FlutterWebviewPlugin.java:133:
warning: [unchecked] unchecked cast
[ +1 ms] Map arguments = (Map) call.arguments;
[ +1 ms] ^
[ ] required: Map
[ +1 ms] found: Object
[ ] C:\src\flutter\.pub-cache\hosted\pub.dartlang.org\flutter_webview_plugin-0.3.11\android\src\main\java\com\flutter_webview_plugin\FlutterWebviewPlugin.java:134:
warning: [unchecked] unchecked conversion
[ +1 ms] List channelNames = new ArrayList();
[ +1 ms] ^
[ ] required: List
[ +1 ms] found: ArrayList
[ +20 ms] C:\src\flutter\.pub-cache\hosted\pub.dartlang.org\flutter_webview_plugin-0.3.11\android\src\main\java\com\flutter_webview_plugin\FlutterWebviewPlugin.java:136:
warning: [unchecked] unchecked cast
[ +12 ms] channelNames = (List) arguments.get(JS_CHANNEL_NAMES_FIELD);
[ +1 ms] ^
[ +1 ms] required: List
[ ] found: Object
[ +1 ms] C:\src\flutter\.pub-cache\hosted\pub.dartlang.org\flutter_webview_plugin-0.3.11\android\src\main\java\com\flutter_webview_plugin\FlutterWebviewPlugin.java:310:
warning: [deprecation] removeAllCookie() in CookieManager has been deprecated
[ +1 ms] CookieManager.getInstance().removeAllCookie();
[ +1 ms] ^
[ ] C:\src\flutter\.pub-cache\hosted\pub.dartlang.org\flutter_webview_plugin-0.3.11\android\src\main\java\com\flutter_webview_plugin\WebviewManager.java:193: warning:
[unchecked] unchecked conversion
[ +4 ms] mUploadMessage = uploadMsg;
[ +1 ms] ^
[ ] required: ValueCallback
[ ] found: ValueCallback
[ +1 ms] C:\src\flutter\.pub-cache\hosted\pub.dartlang.org\flutter_webview_plugin-0.3.11\android\src\main\java\com\flutter_webview_plugin\WebviewManager.java:346: warning:
[deprecation] removeAllCookie() in CookieManager has been deprecated
[ +1 ms] CookieManager.getInstance().removeAllCookie();
[ ] ^
[ +1 ms] 9 warnings

Tái hiện quá trình build APK Android với flutter_webview_plugin 0.3.11 và chạy lệnh flutter analyze đã được báo cáo. Bắt đầu với BrowserClient.java, FlutterWebviewPlugin.java và WebviewManager.java, nơi log hiển thị các cảnh báo deprecated và unchecked. Hoàn tất khi xác định được lỗi build thực tế và xác nhận rằng APK Android được build thành công.

Do mô hình lập chỉ mục viết ra từ nội dung của issue.