dart2dart: Implementation of simple try/catch.

pkg/compiler/lib/src/dart_backend/backend_ast_to_frontend_ast.dart

Index: pkg/compiler/lib/src/dart_backend/backend_ast_to_frontend_ast.dart
diff --git a/pkg/compiler/lib/src/dart_backend/backend_ast_to_frontend_ast.dart b/pkg/compiler/lib/src/dart_backend/backend_ast_to_frontend_ast.dart
index 373ccfd41371b09a8ff9ab8362225da3afd68a8f..8398cbbdb8ad0ab63e102454b5940874c06a4ac8 100644
--- a/pkg/compiler/lib/src/dart_backend/backend_ast_to_frontend_ast.dart
+++ b/pkg/compiler/lib/src/dart_backend/backend_ast_to_frontend_ast.dart
@@ -840,10 +840,10 @@ class TreePrinter {
     } else if (stmt is Try) {
       return new tree.TryStatement(
           makeBlock(stmt.tryBlock),
-          braceList('', stmt.catchBlocks.map(makeCatchBlock)),
+          makeList(null, stmt.catchBlocks.map(makeCatchBlock)),
           stmt.finallyBlock == null ? null : makeBlock(stmt.finallyBlock),
           tryToken,
-          finallyToken);
+          stmt.finallyBlock == null ? null : finallyToken);
     } else if (stmt is VariableDeclarations) {
       return makeVariableDeclarations(stmt, useVar: true, endToken: semicolon);
     } else if (stmt is While) {
@@ -890,16 +890,20 @@ class TreePrinter {
   tree.CatchBlock makeCatchBlock(CatchBlock block) {
     List<tree.VariableDefinitions> formals = [];
     if (block.exceptionVar != null) {
+      tree.Node exceptionName = makeIdentifier(block.exceptionVar.name);
+      setElement(exceptionName, block.exceptionVar.element, block.exceptionVar);
       formals.add(new tree.VariableDefinitions(
           null,
           makeEmptyModifiers(),
-          singleton(makeIdentifier(block.exceptionVar))));
+          singleton(exceptionName)));
     }
     if (block.stackVar != null) {
+      tree.Node stackTraceName = makeIdentifier(block.stackVar.name);
+      setElement(stackTraceName, block.stackVar.element, block.stackVar);
       formals.add(new tree.VariableDefinitions(
           null,
           makeEmptyModifiers(),
-          singleton(makeIdentifier(block.stackVar))));
+          singleton(stackTraceName)));
     }
     return new tree.CatchBlock(
         block.onType == null ? null : makeType(block.onType),