Fix checkedInstructionOrNonGenerateAtUseSite.

sdk/lib/_internal/compiler/implementation/ssa/codegen_helpers.dart

Index: sdk/lib/_internal/compiler/implementation/ssa/codegen_helpers.dart
diff --git a/sdk/lib/_internal/compiler/implementation/ssa/codegen_helpers.dart b/sdk/lib/_internal/compiler/implementation/ssa/codegen_helpers.dart
index 2caf6410e93999ea6cf039426b1dda21cbc461fa..97628a04c0a5b4a0a03e17db2baa7f914345f9bc 100644
--- a/sdk/lib/_internal/compiler/implementation/ssa/codegen_helpers.dart
+++ b/sdk/lib/_internal/compiler/implementation/ssa/codegen_helpers.dart
@@ -116,11 +116,7 @@ class SsaInstructionSelection extends HBaseVisitor {
         HInstruction interceptor = node.inputs[0];
         HInstruction receiverArgument = node.inputs[1];
 
-        // TODO(15720): The test here should be
-        //
-        //     interceptor.nonCheck() == receiverArgument.nonCheck()
-        //
-        if (interceptor == receiverArgument) {
+        if (interceptor.nonCheck() == receiverArgument.nonCheck()) {
           // TODO(15933): Make automatically generated property extraction
           // closures work with the dummy receiver optimization.
           if (!selector.isGetter()) {