Handle exception and clean-up code

pkg/analyzer/lib/src/generated/engine.dart

 // Copyright (c) 2014, 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.
 
 // This code was auto-generated, is not intended to be edited, and is subject to
 // significant change. Please see the README file for more information.
 
 library engine;
 
 import "dart:math" as math;
@@ skipping 1959 matching lines @@
           if (element == null) {
             return null;
           }
           element = element.getChild(components[i]);
         }
         return element;
       }
       if (AnalysisEngine.isHtmlFileName(sourceName)) {
         return computeHtmlElement(source);
       }
-    } on AnalysisException catch (exception) {
+    } catch (exception) {
+      // If the location cannot be decoded for some reason then the underlying
+      // cause should have been logged already and we can fall though to return
+      // null.
     }
     return null;
   }
 
   @override
   AnalysisErrorInfo getErrors(Source source) {
     SourceEntry sourceEntry = getReadableSourceEntryOrNull(source);
     if (sourceEntry is DartEntry) {
       DartEntry dartEntry = sourceEntry;
       return new AnalysisErrorInfoImpl(
@@ skipping 10377 matching lines @@
     if (element.id == _id) {
       result = element;
       throw new _ElementByIdFinderException();
     }
     super.visitElement(element);
   }
 }
 
 class _ElementByIdFinderException {
 }