Implement type inference for try/catch blocks.

pkg/front_end/lib/src/fasta/type_inference/type_inference_listener.dart

Index: pkg/front_end/lib/src/fasta/type_inference/type_inference_listener.dart
diff --git a/pkg/front_end/lib/src/fasta/type_inference/type_inference_listener.dart b/pkg/front_end/lib/src/fasta/type_inference/type_inference_listener.dart
index ac29a1e1235bc98bc1efecf2c4773b10d0320b63..cf509489f2a4bf33239217ea39ecc73cf0b1f7b5 100644
--- a/pkg/front_end/lib/src/fasta/type_inference/type_inference_listener.dart
+++ b/pkg/front_end/lib/src/fasta/type_inference/type_inference_listener.dart
@@ -322,6 +322,18 @@ class TypeInferenceListener
   void throwExit(Throw expression, DartType inferredType) =>
       debugExpressionExit('throw', expression, inferredType);
 
+  void tryCatchEnter(TryCatch statement) =>
+      debugStatementEnter('tryCatch', statement);
+
+  void tryCatchExit(TryCatch statement) =>
+      debugStatementExit('tryCatch', statement);
+
+  void tryFinallyEnter(TryFinally statement) =>
+      debugStatementEnter('tryFinally', statement);
+
+  void tryFinallyExit(TryFinally statement) =>
+      debugStatementExit('tryFinally', statement);
+
   bool variableAssignEnter(Expression expression, DartType typeContext) =>
       debugExpressionEnter("variableAssign", expression, typeContext);