[MaterialTimePicker] Does not respect isCancelable / setCancelable

[tinacious]

Description: The MaterialTimePicker component does not respect the isCancelable property (setCancelable) in the following ways:

• the cancel button is still visible
• the dialog gets dismissed after pressing Cancel

Expected behavior: It is expected that the Cancel button not be visible so that cancel listeners would not be called and the dialog would not be dismissed.

Working around this bug adds complexity at the implementation side.

Source code:

material-components-android/lib/java/com/google/android/material/timepicker/MaterialTimePicker.java

Lines 249 to 259 in a009557

	Button cancelButton = root.findViewById(R.id.material_timepicker_cancel_button);
	cancelButton.setOnClickListener(
	new OnClickListener() {
	@Override
	public void onClick(View v) {
	for (OnClickListener listener : negativeButtonListeners) {
	listener.onClick(v);
	}
	dismiss();
	}
	});

Android API version: 8.1.0, 11

Material Library version: 1.3.0 (latest stable release)

Device: Nexus 5X, Pixel 4a

Thank you!