[webview_flutter_android] Implementation of Android WebView widget using pigeon (#4503)

Author: bparrishMines

packages/webview_flutter/analysis_options.yaml

@@ -0,0 +1 @@
+include: ../../../analysis_options_legacy.yaml

packages/webview_flutter/webview_flutter/analysis_options.yaml

@@ -197,9 +197,11 @@ void main() {
       onPageFinished: () => onPageFinished.complete(),
     ));
     await onPageFinished.future;
-    if (Platform.isAndroid) {
-      await initialResizeCompleter.future;
-    }
+    // Wait for a potential call to resize after page is loaded.
+    await initialResizeCompleter.future.timeout(
+      const Duration(seconds: 3),
+      onTimeout: () => null,
+    );
 
     resizeButtonTapped = true;
     await tester.tap(find.byKey(const ValueKey('resizeButton')));

packages/webview_flutter/webview_flutter/example/integration_test/webview_flutter_test.dart

@@ -1,3 +1,7 @@
+## 2.3.0
+
+* Replaces platform implementation with API built with pigeon.
+
 ## 2.2.1
 
 * Fix `NullPointerException` from a race condition when changing focus. This only affects `WebView`