Don't recreate CoreTypes in transformers. Pass it in.

pkg/analyzer/lib/src/fasta/analyzer_loader.dart

Index: pkg/analyzer/lib/src/fasta/analyzer_loader.dart
diff --git a/pkg/analyzer/lib/src/fasta/analyzer_loader.dart b/pkg/analyzer/lib/src/fasta/analyzer_loader.dart
index 49f754364bb93e9fc3792a3a16c6cb146ec79970..0fee12c232234e5d18a54314e8c4466a30a4b862 100644
--- a/pkg/analyzer/lib/src/fasta/analyzer_loader.dart
+++ b/pkg/analyzer/lib/src/fasta/analyzer_loader.dart
@@ -22,6 +22,8 @@ import 'package:analyzer/src/fasta/element_store.dart' show ElementStore;
 
 import 'analyzer_diet_listener.dart' show AnalyzerDietListener;
 
+import 'package:kernel/core_types.dart' show CoreTypes;
+
 class AnalyzerLoader<L> extends SourceLoader<L> {
   ElementStore elementStore;
 
@@ -32,6 +34,7 @@ class AnalyzerLoader<L> extends SourceLoader<L> {
   void computeHierarchy(Program program) {
     elementStore = new ElementStore(coreLibrary, builders);
     ticker.logMs("Built analyzer element model.");
+    coreTypes = new CoreTypes(program);

[ahe, 2017/05/29 14:08:46]

Add:

    ticker.logMs("Computed core types");

[scheglov, 2017/05/30 00:06:10]

I will, but I'm curious what the purpose of this logging.
Given that creating of CoreTypes is very cheap now, and is done lazily, we
neither measure time spent, nor verify that some step is successfully performed.

[ahe, 2017/05/30 09:35:14]

The only way to tell if no time is being spent computing core types is to log
it.

If you don't call the log method, the time (however minuscule) will be
attributed incorrectly to the next phase. So to be able to correctly analyze the
time spent in each phase, it's important that logMs is called at the end of the
phase.

If we don't call log here and someone slows down CoreTypes, we may not notice
it.

You might argue that we can just get those numbers by using the observatory, but
that's not entirely correct. The profiler in the observatory doesn't work well
for measuring short-running programs that may not have been fully optimized yet.

[scheglov, 2017/05/30 16:10:21]

I will not argue with this, you're right Observatory.

OK, now I understand why we need to log here.
Thank you.

   }
 
   @override