Include import prefixes on type error messages - dart2js

[srawlins]

Similar to #33667 (CFE), #33693 (VM), and #33695 (DDC).

Here's a dartpad. Code:

import 'dart:math' as math;

// Poorly named wrapper for math.Random
class Random {
  math.Random inner;

  Random(this.inner);
}

void main() {
  List<Random> list = new List<Random>()..add(new Random(new math.Random(7)));
  addRandom(list.map((e) => e.inner));
}

addRandom(List<math.Random> list) => list..add(new math.Random());

Here's the runtime error:

Uncaught exception:
TypeError: Instance of 'MappedListIterable<Random, Random0>': type 'MappedListIterable<Random, Random0>' is not a subtype of type 'List<Random0>'

Instead of Random0 (or in addition, whatever). It'd be nice if the error respected the prefixes that the user uses in their code, a step they've already taken to de-conflate the two classes, to read:

Uncaught exception:
TypeError: Instance of 'MappedListIterable<Random, math.Random>': type 'MappedListIterable<Random, math.Random>' is not a subtype of type 'List<math.Random>'

Or if its easier to not include a ., this would be fine:

Uncaught exception:
TypeError: Instance of 'MappedListIterable<Random, math_Random>': type 'MappedListIterable<Random, math_Random>' is not a subtype of type 'List<math_Random>'