Update corelib/ and lib/ to use the new try-catch syntax.

lib/compiler/implementation/scanner/scanner_task.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 class ScannerTask extends CompilerTask {
   ScannerTask(Compiler compiler) : super(compiler);
   String get name => 'Scanner';
 
   void scanLibrary(LibraryElement library) {
     var compilationUnit = library.entryCompilationUnit;
@@ skipping 97 matching lines @@
                   tag,
                   compilationUnit);
     return resolved;
   }
 
   void scanElements(CompilationUnitElement compilationUnit) {
     Script script = compilationUnit.script;
     Token tokens;
     try {
       tokens = new StringScanner(script.text).tokenize();
-    } catch (MalformedInputException ex) {
+    } on MalformedInputException catch (ex) {
       Token token;
       var message;
       if (ex.position is num) {
         // TODO(ahe): Always use tokens in MalformedInputException.
         token = new Token(EOF_INFO, ex.position);
       } else {
         token = ex.position;
       }
       compiler.cancel(ex.message, token: token);
     }
@@ skipping 97 matching lines @@
   static const int RESOURCE = 4;
 
   /** Next state. */
   static const List<int> NEXT =
       const <int>[NO_TAG_SEEN,
                   IMPORT, // Only one library tag is allowed.
                   IMPORT,
                   SOURCE,
                   RESOURCE];
 }