8318468: compiler/tiered/LevelTransitionTest.java fails with...

8318468: compiler/tiered/LevelTransitionTest.java fails with -XX:CompileThreshold=100 -XX:TieredStopAtLevel=1

Backport-of: 61d0db3838932d4030b05ffb04ee2b0215ea686e

test/hotspot/jtreg/compiler/tiered/LevelTransitionTest.java

@@ -204,7 +204,8 @@ public class LevelTransitionTest extends TieredLevelsTest {
         }
 
         private static class CompileMethodHolder {
-            private final int iter = 10;
+            // Make sure that loop backedge is never taken to prevent unexpected OSR compilations.
+            private final int iter = 1;
             private int field = 42;
 
             /**