Remove separate label field from PatchSetApproval

This is now stored directly in the key.

Change-Id: I9c53e6a08fb4de17e8faa1153f85f5226a3a51fb
diff --git a/gerrit-reviewdb/src/main/java/com/google/gerrit/reviewdb/client/PatchSetApproval.java b/gerrit-reviewdb/src/main/java/com/google/gerrit/reviewdb/client/PatchSetApproval.java
index cdd9fae..8d79d66 100644
--- a/gerrit-reviewdb/src/main/java/com/google/gerrit/reviewdb/client/PatchSetApproval.java
+++ b/gerrit-reviewdb/src/main/java/com/google/gerrit/reviewdb/client/PatchSetApproval.java
@@ -137,9 +137,6 @@
   @Column(id = 5, length = 16, notNull = false)
   protected String changeSortKey;
 
-  /** Label name copied from corresponding {@link ApprovalCategory}. */
-  protected String label;
-
   protected PatchSetApproval() {
   }
 
@@ -200,15 +197,11 @@
   }
 
   public String getLabel() {
-    return label;
-  }
-
-  public void setLabel(String label) {
-    this.label = label;
+    return getLabelId().get();
   }
 
   public boolean isSubmit() {
-    return LabelId.SUBMIT.get().equals(getLabelId().get());
+    return LabelId.SUBMIT.get().equals(getLabel());
   }
 
   @Override
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/git/LabelNormalizer.java b/gerrit-server/src/main/java/com/google/gerrit/server/git/LabelNormalizer.java
index 6411289..3f09916 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/git/LabelNormalizer.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/git/LabelNormalizer.java
@@ -108,7 +108,6 @@
   private PatchSetApproval copy(PatchSetApproval src, ChangeControl ctl) {
     PatchSetApproval dest = new PatchSetApproval(src.getPatchSetId(), src);
     dest.cache(ctl.getChange());
-    dest.setLabel(src.getLabel());
     return dest;
   }