Remove height styling when keyboard closed (#16965)

Summary:
Closes #13754

Fixing previously reported bug #13754

Video here https://imgur.com/a/3IgqP

[GENERAL] [BUGFIX] [KeyboardAvoidingView] - Correct height behaviour when keyboard closed
Pull Request resolved: #16965

Differential Revision: D13860208

Pulled By: cpojer

fbshipit-source-id: 9ae7f81fd24999518a6ae85016d4f75dac3c4274

Libraries/Components/Keyboard/KeyboardAvoidingView.js

@@ -160,7 +160,7 @@ class KeyboardAvoidingView extends React.Component<Props, State> {
     switch (behavior) {
       case 'height':
         let heightStyle;
-        if (this._frame != null) {
+        if (this._frame != null && this.state.bottom > 0) {
           // Note that we only apply a height change when there is keyboard present,
           // i.e. this.state.bottom is greater than 0. If we remove that condition,
           // this.frame.height will never go back to its original value.