Backported refinements and polishing

spring-expression/src/main/java/org/springframework/expression/spel/ast/Indexer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2016 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -694,7 +694,7 @@ public class Indexer extends SpelNodeImpl {
 						newElements--;
 					}
 				}
-				catch (Exception ex) {
+				catch (Throwable ex) {
 					throw new SpelEvaluationException(getStartPosition(), ex, SpelMessage.UNABLE_TO_GROW_COLLECTION);
 				}
 			}