Added javadoc for getExtraSourceLocations()

bridge/src/org/aspectj/bridge/IMessage.java

@@ -125,5 +125,18 @@ public interface IMessage {
 	 */
 	public String getDetails();
     
+	
+	/** 
+	 * @return List of <code>ISourceLocation</code> instances that indicate 
+	 * additional source locations relevent to this message as specified by the 
+	 * message creator. The list should not include the primary source location 
+	 * associated with the message which can be obtained from 
+	 * <code>getSourceLocation()<code>. 
+	 * <p>   
+	 * An example of using extra locations would be in a warning message that 
+	 * flags all shadow locations that will go unmatched due to a pointcut definition 
+	 * being based on a subtype of a defining type. 
+	 * @see <a href="https://bugs.eclipse.org/bugs/show_bug.cgi?id=41952">AspectJ bug 41952</a> 
+	 */ 
     public List getExtraSourceLocations();
 }