Move QueryBuilder.badFieldType to FieldType class

This allows the method to be used without having a dependency on the
gerrit-lucene module, which in turn has a dependency on a specific
version of Lucene.

Change-Id: I57e92c71260a51327ed706bd65f8f9e384e15666

gerrit-lucene/src/main/java/com/google/gerrit/lucene/LuceneChangeIndex.java

@@ -554,7 +554,7 @@ public class LuceneChangeIndex implements ChangeIndex {
         doc.add(new StoredField(name, (byte[]) value));
       }
     } else {
-      throw QueryBuilder.badFieldType(type);
+      throw FieldType.badFieldType(type);
     }
   }
 

gerrit-lucene/src/main/java/com/google/gerrit/lucene/QueryBuilder.java

@@ -148,7 +148,7 @@ public class QueryBuilder {
     } else if (p.getType() == FieldType.FULL_TEXT) {
       return fullTextQuery(p);
     } else {
-      throw badFieldType(p.getType());
+      throw FieldType.badFieldType(p.getType());
     }
   }
 
@@ -249,8 +249,4 @@ public class QueryBuilder {
   public int toIndexTimeInMinutes(Date ts) {
     return (int) (ts.getTime() / 60000);
   }
-
-  public static IllegalArgumentException badFieldType(FieldType<?> t) {
-    return new IllegalArgumentException("unknown index field type " + t);
-  }
 }