Instrument analyzer's type analysis and run front_end inference tests.

pkg/front_end/lib/src/fasta/testing/validating_instrumentation.dart

Index: pkg/front_end/lib/src/fasta/testing/validating_instrumentation.dart
diff --git a/pkg/front_end/lib/src/fasta/testing/validating_instrumentation.dart b/pkg/front_end/lib/src/fasta/testing/validating_instrumentation.dart
index 19b86eb9a0fe1e9a1455357b87bdb6ec050fe8af..ca7810ad2e82a8450ff17e3b3b499f5ad9c0ac99 100644
--- a/pkg/front_end/lib/src/fasta/testing/validating_instrumentation.dart
+++ b/pkg/front_end/lib/src/fasta/testing/validating_instrumentation.dart
@@ -78,7 +78,7 @@ class ValidatingInstrumentation implements Instrumentation {
     var fixes = _fixes[uri];
     if (fixes == null) return;
     File file = new File.fromUri(uri);
-    var bytes = await file.readAsBytes();
+    var bytes = (await file.readAsBytes()).toList();
     // Apply the fixes in reverse order so that offsets don't need to be
     // adjusted after each fix.
     fixes.sort((a, b) => b.offset.compareTo(a.offset));