LogThreshold: Allow the annotation to be inherited

With the current implementation the log threshold is only set when the
annotation is done on the exact class, which means that in cases where
an abstract test class is extended by several derived test classes, it
is necessary to add the annotation on each derived class individually.

Allow the annotation to be inherited, so that it is possible to only
annotate the base class, and it will also be effective for all derived
classes.

Change-Id: I0501b2a617161a391478313b6f9891108bdf9969
diff --git a/java/com/google/gerrit/acceptance/LogThreshold.java b/java/com/google/gerrit/acceptance/LogThreshold.java
index da1fcc5..36831f3 100644
--- a/java/com/google/gerrit/acceptance/LogThreshold.java
+++ b/java/com/google/gerrit/acceptance/LogThreshold.java
@@ -17,11 +17,13 @@
 import static java.lang.annotation.ElementType.TYPE;
 import static java.lang.annotation.RetentionPolicy.RUNTIME;
 
+import java.lang.annotation.Inherited;
 import java.lang.annotation.Retention;
 import java.lang.annotation.Target;
 
 @Target({TYPE, METHOD})
 @Retention(RUNTIME)
+@Inherited
 public @interface LogThreshold {
   String level() default "DEBUG";
 }