8066843: Messager.printMessage cannot print multiple errors for same source position Summary: Using a DiagnosticFlag to mark diagnostics that should be always printed even if multiple of them have the same source position. Reviewed-by: darcy, jjg, mcimadamore

AnchorAlreadyDefined.java:14: error: anchor already defined: "here"
 * <a name="here">duplicate</a>
      ^
AnchorAlreadyDefined.java:15: error: anchor already defined: "here"
 * <h1 id="here">duplicate</h1>
       ^
2 errors