hg: jdk/submit: 8146726: Improve AbstractProcessor to issue warnings for repeated information

[joe.darcy at oracle.com]

Changeset: 67b040623a12
Author:    darcy
Date:      2019-05-01 16:47 -0700
URL:       http://hg.openjdk.java.net/jdk/submit/rev/67b040623a12

8146726: Improve AbstractProcessor to issue warnings for repeated information
Reviewed-by: jjg, smarks, serb, igerasim

! src/java.compiler/share/classes/javax/annotation/processing/AbstractProcessor.java
! src/java.compiler/share/classes/javax/annotation/processing/Processor.java
+ test/langtools/tools/javac/processing/warnings/TestRepeatedSupportedItems.java
+ test/langtools/tools/javac/processing/warnings/au_8.out
+ test/langtools/tools/javac/processing/warnings/au_current.out