Consider using decorator instead prefix and suffix

[vlytvyne]

Interface LookupMessages declares following methods to append "ago" to the formatted time:

/// Example: `prefixAgo()` 1 min `suffixAgo()`
String prefixAgo();

/// Example: `prefixFromNow()` 1 min `suffixFromNow()`
String prefixFromNow();

/// Example: `prefixAgo()` 1 min `suffixAgo()`
String suffixAgo();

/// Example: `prefixFromNow()` 1 min `suffixFromNow()`
String suffixFromNow();

which should be overridden by the client in order to apply custom locale, which is rather inconvenient if you get those locales dynamically. I think that something like decorateWithAgo(String formatted time) might be more flexible as a client doesn't have to worry about providing 2 types of prefixes and 2 types of sufixes (which may or may not be present in some languages) but instead just provide simple realization of decorateWithAgo method.

Please, compare:

@override
String prefixAgo() => 'hace';

@override
String prefixFromNow() => 'dentro de';

@override
String suffixAgo() => '';

@override
String suffixFromNow() => '';

and

@override
String wrapWithAgo(String formattedTime) => 'hace $formattedTime';

Note that the vast majority of people will use either "ago" OR "from now" across all of the app. Also, not all languages really have "from now" analog, which makes prefixFromNow, suffixFromNow not so relevant and rather confusing.

What are your thoughts?