dart2js cps: Do not count refinement nodes when measuring size.

pkg/compiler/lib/src/cps_ir/inline.dart

Index: pkg/compiler/lib/src/cps_ir/inline.dart
diff --git a/pkg/compiler/lib/src/cps_ir/inline.dart b/pkg/compiler/lib/src/cps_ir/inline.dart
index e33438fc71e1b01ae9d3ef9e73a01de72b54d159..cc046eec2c56c6588041c26cee5f3c652ae5b072 100644
--- a/pkg/compiler/lib/src/cps_ir/inline.dart
+++ b/pkg/compiler/lib/src/cps_ir/inline.dart
@@ -220,7 +220,11 @@ class SizeVisitor extends TrampolineRecursiveVisitor {
   // Inlining a function incurs a cost equal to the number of primitives and
   // non-jump tail expressions.
   // TODO(kmillikin): Tune the size computation and size bound.
-  processLetPrim(LetPrim node) => ++size;
+  processLetPrim(LetPrim node) {
+    if (node.primitive is! Refinement) {
+      ++size;
+    }
+  }
   processLetMutable(LetMutable node) => ++size;
   processBranch(Branch node) => ++size;
   processThrow(Throw nose) => ++size;