8244670: convert clhsdb "whatis" command from javascript to java

Backport-of: 00c0d1087021603f3f09131cb0458ac8b9c110e5

Author: Victor Rudometov

test/hotspot/jtreg/serviceability/sa/ClhsdbFindPC.java

@@ -182,6 +182,15 @@ private static void testFindPC(boolean withXcomp, boolean withCore) throws Excep
                                           methodAddr));
             runTest(withCore, cmds, expStrMap);
 
+            // Rerun above findpc command, but this time using "whatis", which is an alias for "findpc".
+            cmdStr = "whatis " + methodAddr;
+            cmds = List.of(cmdStr);
+            expStrMap = new HashMap<>();
+            expStrMap.put(cmdStr, List.of("Method ",
+                                          "LingeredApp.steadyState",
+                                          methodAddr));
+            runTest(withCore, cmds, expStrMap);
+
             // Run findpc on a JavaThread*. We can find one in the jstack output.
             // The tid for a thread is it's JavaThread*. For example:
             //  "main" #1 prio=5 tid=0x00000080263398f0 nid=0x277e0 ...