Fixing layout in js output (use full paths rather than just the library name)

test/codegen/expect/BenchmarkBase/BenchmarkBase.js

-var BenchmarkBase;
-(function(BenchmarkBase) {
-  'use strict';
-  class Expect extends dart.Object {
-    static equals(expected, actual) {
-      if (!dart.equals(expected, actual)) {
-        throw `Values not equal: ${expected} vs ${actual}`;
-      }
-    }
-    static listEquals(expected, actual) {
-      if (expected.length !== actual.length) {
-        throw `Lists have different lengths: ${expected.length} vs ${actual.length}`;
-      }
-      for (let i = 0; i < actual.length; i++) {
-        equals(expected.get(i), actual.get(i));
-      }
-    }
-    fail(message) {
-      throw message;
-    }
-  }
-  class BenchmarkBase extends dart.Object {
-    BenchmarkBase(name) {
-      this.name = name;
-    }
-    run() {}
-    warmup() {
-      this.run();
-    }
-    exercise() {
-      for (let i = 0; i < 10; i++) {
-        this.run();
-      }
-    }
-    setup() {}
-    teardown() {}
-    static measureFor(f, timeMinimum) {
-      let time = 0;
-      let iter = 0;
-      let watch = new core.Stopwatch();
-      watch.start();
-      let elapsed = 0;
-      while (elapsed < timeMinimum) {
-        dart.dinvokef(f);
-        elapsed = watch.elapsedMilliseconds;
-        iter++;
-      }
-      return 1000.0 * elapsed / iter;
-    }
-    measure() {
-      this.setup();
-      measureFor((() => {
-        this.warmup();
-      }).bind(this), 100);
-      let result = measureFor((() => {
-        this.exercise();
-      }).bind(this), 2000);
-      this.teardown();
-      return result;
-    }
-    report() {
-      let score = this.measure();
-      core.print(`${this.name}(RunTime): ${score} us.`);
-    }
-  }
-  // Exports:
-  BenchmarkBase.Expect = Expect;
-  BenchmarkBase.BenchmarkBase = BenchmarkBase;
-})(BenchmarkBase || (BenchmarkBase = {}));