[webview_flutter] Add keyboard info to the README (#1910)

Adds list of specific known issues.

packages/webview_flutter/CHANGELOG.md

diff --git a/packages/webview_flutter/CHANGELOG.md b/packages/webview_flutter/CHANGELOG.md
index 7904efa..d8a4808 100644
--- a/packages/webview_flutter/CHANGELOG.md
+++ b/packages/webview_flutter/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 0.3.10+4
+
+* Add keyboard text to README.
+
 ## 0.3.10+3
 
 * Don't log an unknown setting key error for 'debuggingEnabled' on iOS.

packages/webview_flutter/README.md

diff --git a/packages/webview_flutter/README.md b/packages/webview_flutter/README.md
index 948d90d..8e8d397 100644
--- a/packages/webview_flutter/README.md
+++ b/packages/webview_flutter/README.md
@@ -18,6 +18,17 @@
 adding a boolean property to the app's `Info.plist` file, with the key `io.flutter.embedded_views_preview`
 and the value `YES`.
 
+Keyboard support within webviews is also experimental. The above tags also
+surface known issues with keyboard input. Some currently known keyboard issues,
+as of `webview_flutter` version `0.3.10+4`:
+
+* [Input needs to be tapped twice to be registered on Samsung
+  devices](https://github.com/flutter/flutter/issues/35867)
+* [Keyboard behavior is buggy after a
+  resize](https://github.com/flutter/flutter/issues/36978)
+* [Keyboard persists after tapping outside text
+  field](https://github.com/flutter/flutter/issues/36478)
+
 ## Setup
 
 ### iOS

packages/webview_flutter/pubspec.yaml

diff --git a/packages/webview_flutter/pubspec.yaml b/packages/webview_flutter/pubspec.yaml
index 4d230df..38033b7 100644
--- a/packages/webview_flutter/pubspec.yaml
+++ b/packages/webview_flutter/pubspec.yaml
@@ -1,6 +1,6 @@
 name: webview_flutter
 description: A Flutter plugin that provides a WebView widget on Android and iOS.
-version: 0.3.10+3
+version: 0.3.10+4
 author: Flutter Team <flutter-dev@googlegroups.com>
 homepage: https://github.com/flutter/plugins/tree/master/packages/webview_flutter