Is there an existing issue for this?

• I have searched the existing issues
• I have read the guide to filing a bug

Use case

iOS has UIKeyboardTypeASCIICapable, but Flutter missing this type.

typedef NS_ENUM(NSInteger, UIKeyboardType) {
UIKeyboardTypeDefault, // Default type for the current input method.
UIKeyboardTypeASCIICapable, // Displays a keyboard which can enter ASCII characters
UIKeyboardTypeNumbersAndPunctuation, // Numbers and assorted punctuation.
UIKeyboardTypeURL, // A type optimized for URL entry (shows . / .com prominently).
UIKeyboardTypeNumberPad, // A number pad with locale-appropriate digits (0-9, ۰-۹, ०-९, etc.). Suitable for PIN entry.
UIKeyboardTypePhonePad, // A phone pad (1-9, *, 0, #, with letters under the numbers).
UIKeyboardTypeNamePhonePad, // A type optimized for entering a person's name or phone number.
UIKeyboardTypeEmailAddress, // A type optimized for multiple email address entry (shows space @ . prominently).
UIKeyboardTypeDecimalPad API_AVAILABLE(ios(4.1)), // A number pad with a decimal point.
UIKeyboardTypeTwitter API_AVAILABLE(ios(5.0)), // A type optimized for twitter text entry (easy access to @ #)
UIKeyboardTypeWebSearch API_AVAILABLE(ios(7.0)), // A default keyboard type with URL-oriented addition (shows space . prominently).
UIKeyboardTypeASCIICapableNumberPad API_AVAILABLE(ios(10.0)), // A number pad (0-9) that will always be ASCII digits.

UIKeyboardTypeAlphabet = UIKeyboardTypeASCIICapable, // Deprecated

};

Proposal

maybe Flutter can add this type

class TextInputType {
static const TextInputType asciiCapble = TextInputType._(11);
}