Draft status patchset and change prefilter

Prefilters patchsets and change messages when generating ChangeDetails
based on whether or not the current user can see a draft status
patchset. Also prefilters changes based on draft change status and
user status in ChangeList. Clients will only receive patchsets or
changes that they can see.

Change-Id: I14434e7907fd23cb036cd231684b04b7983f2087

gerrit-common/src/main/java/com/google/gerrit/common/data/ChangeDetail.java

@@ -188,6 +188,10 @@ public class ChangeDetail {
     currentDetail = d;
   }
 
+  public void setCurrentPatchSetId(final PatchSet.Id id) {
+    currentPatchSetId = id;
+  }
+
   public String getDescription() {
     return currentDetail != null ? currentDetail.getInfo().getMessage() : "";
   }