8154976: UseSharedSpaces error message is incomplete

Reviewed-by: cjplummer, jiangli, mseledtsov

hotspot/src/share/vm/memory/filemap.cpp

@@ -99,7 +99,8 @@ void FileMapInfo::fail_continue(const char *msg, ...) {
       fail(msg, ap);
     } else {
       if (PrintSharedSpaces) {
-        tty->print_cr("UseSharedSpaces: %s", msg);
+        tty->print("UseSharedSpaces: ");
+        tty->vprint_cr(msg, ap);
       }
     }
     UseSharedSpaces = false;

hotspot/test/runtime/CDSCompressedKPtrs/XShareAuto.java

@@ -67,6 +67,7 @@ public class XShareAuto {
             // if sharing failed due to ASLR or similar reasons,
             // check whether sharing was attempted at all (UseSharedSpaces)
             output.shouldContain("UseSharedSpaces:");
+            output.shouldNotContain("Unable to map %s");
         }
         output.shouldHaveExitValue(0);
     }