Use backend targets to run Kernel transformations in Fasta

pkg/front_end/lib/src/fasta/kernel/kernel_target.dart

Index: pkg/front_end/lib/src/fasta/kernel/kernel_target.dart
diff --git a/pkg/front_end/lib/src/fasta/kernel/kernel_target.dart b/pkg/front_end/lib/src/fasta/kernel/kernel_target.dart
index 88cea4b0b140dcd2ade6ba3506206afe400f63ec..af37585f0105663c47fed5115d5833631ec21397 100644
--- a/pkg/front_end/lib/src/fasta/kernel/kernel_target.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/kernel_target.dart
@@ -654,24 +654,9 @@ class KernelTarget extends TargetImplementation {
   /// Run all transformations that are needed when building a program for the
   /// first time.
   void runBuildTransformations() {
-    transformMixinApplications();
-    otherTransformations();
-  }
-
-  void transformMixinApplications() {
-    mix.transformLibraries(backendTarget, loader.coreTypes, loader.libraries);
-    ticker.logMs("Transformed mixin applications");
-  }
-
-  void otherTransformations() {
-    // TODO(ahe): Don't generate type variables in the first place.
-    if (!strongMode) {
-      _program.accept(new Erasure());
-      ticker.logMs("Erased type variables in generic methods");
-    }
-    // TODO(kmillikin): Make this run on a per-method basis.
-    transformAsync.transformLibraries(loader.coreTypes, loader.libraries);
-    ticker.logMs("Transformed async methods");
+    backendTarget.performModularTransformationsOnLibraries(
+        loader.coreTypes, loader.libraries,
+        logger: (String msg) => ticker.logMs(msg));

[ahe, 2017/06/01 11:44:54]

Nice touch keeping the logging!

   }
 
   void verify() {