bug(developer): kmc-ldml should warn if >1 touch layers with no minDeviceWidth attributes

[mcdurdin]

See CLDR-19755

• If >1 touch layer then at least 1 needs minDeviceWidth.
• No 2 layers should have same minDeviceWidth (incl. inferred; this may catch point 1 above)
• Probably, hint if hardware form has minDeviceWidth

[mcdurdin]

proposal notes

layr.ts:

// implement:
// TODO-LDML: CLDR-19754 spec does not require minDeviceWidth, but if multiple touch forms then it would be important for differentiation


// line 62 approx, hardware path, add:

if(typeof layers.minDeviceWidth !== 'undefined') {
  this.callbacks.reportMessage(LdmlCompilerMessages.Warn_HardwareFormShouldNotHaveMinDeviceWidth({formId}, layers));
}

ldml-compiler-messages.ts, add:

  static HINT_HardwareFormShouldNotHaveMinDeviceWidth = SevHint | 0x0035;
  static Hint_HardwareFormShouldNotHaveMinDeviceWidth = (o: { formId: string }, compileContext?: ObjectWithCompileContext) => mx(
    this.HINT_HardwareFormShouldNotHaveMinDeviceWidth, compileContext,
    `Hardware form "${def(o.formId)}" should not have a "minDeviceWidth" attribute`, `
    Touch forms should have a \`minDeviceWidth\` attribute, but this is not
    appropriate for a hardware form. Do not mix hardware and touch data.
  `);

layr.tests.ts, add:

    {
      subpath: 'sections/layr/hint-hardware-form-should-not-have-min-device-width.xml',
      errors: [
        LdmlCompilerMessages.Hint_HardwareFormShouldNotHaveMinDeviceWidth({formId: 'iso'}),
      ]
    },

// also, test for multiple touch forms without minDeviceWidth