PasswordInput: Use Pressable for show/hide icon button

This lets us have a more compact layout (e.g., the left edge of the
icon is just 8px away from the right edge of the password input,
instead of that 8px plus 12px of padding in the Touchable) while
maintaining the 48px touch-target size with the help of `hitSlop`.

src/common/PasswordInput.js

@@ -1,24 +1,17 @@
 /* @flow strict-local */
 import React, { useState, useCallback } from 'react';
 import type { Node } from 'react';
-import { View } from 'react-native';
+import { View, Pressable } from 'react-native';
 
 import { Icon } from './Icons';
 import Input from './Input';
 import type { Props as InputProps } from './Input';
-import { BRAND_COLOR, createStyleSheet } from '../styles';
-import Touchable from './Touchable';
+import { BRAND_COLOR, HIGHLIGHT_COLOR, createStyleSheet } from '../styles';
 
 const styles = createStyleSheet({
   showPasswordButton: {
     marginLeft: 8,
   },
-  showPasswordButtonIcon: {
-    // 24 (icon size) + 12 + 12 = 48px min touch target:
-    //   https://material.io/design/usability/accessibility.html#layout-and-typography
-    margin: 12,
-    color: BRAND_COLOR,
-  },
   passwordTextInput: {
     flex: 1,
   },
@@ -57,9 +50,21 @@ export default function PasswordInput(props: Props): Node {
         autoCapitalize="none"
         style={styles.passwordTextInput}
       />
-      <Touchable style={styles.showPasswordButton} onPress={handleShow}>
-        <Icon name={isHidden ? 'eye-off' : 'eye'} size={24} style={styles.showPasswordButtonIcon} />
-      </Touchable>
+      <Pressable
+        // 24 (icon size) + 12 + 12 = 48px min touch target:
+        //   https://material.io/design/usability/accessibility.html#layout-and-typography
+        hitSlop={12}
+        style={styles.showPasswordButton}
+        onPress={handleShow}
+      >
+        {({ pressed }) => (
+          <Icon
+            color={pressed ? HIGHLIGHT_COLOR : BRAND_COLOR}
+            name={isHidden ? 'eye-off' : 'eye'}
+            size={24}
+          />
+        )}
+      </Pressable>
     </View>
   );
 }