Review of r1539036 by Nick Williams.

copyWithoutTransformers(), as defined in the interface InstrumentableClassLoader, returns a ClassLoader. The start() method is not defined in ClassLoader, it is specific to WebappClassLoader. Furthermore, code calling copyWithoutTransformers() won't have access to WebappClassLoader to call start() reflectively if a SecurityManager is enabled.

So, the copyWithoutTransformers() method needs to call start() before it returns the copied class loader. Otherwise, it will be useless to JPA providers and the like.

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1539180 13f79535-47bb-0310-9956-ffa450edef68