ChangeIndexRewriter: Add missing type arguments for generic classes

This fixes Eclipse and ErrorProne warnings.

Change-Id: I33d23a5d99ac07feedc0c664fffe1a187a8f5f7f
Signed-off-by: Edwin Kempin <ekempin@google.com>

gerrit-server/src/main/java/com/google/gerrit/server/index/change/ChangeIndexRewriter.java

diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/index/change/ChangeIndexRewriter.java b/gerrit-server/src/main/java/com/google/gerrit/server/index/change/ChangeIndexRewriter.java
index 437af65..ca80131 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/index/change/ChangeIndexRewriter.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/index/change/ChangeIndexRewriter.java
@@ -229,8 +229,8 @@
     }
     IndexPredicate<ChangeData> p = (IndexPredicate<ChangeData>) in;
 
-    FieldDef def = p.getField();
-    Schema schema = index.getSchema();
+    FieldDef<ChangeData, ?> def = p.getField();
+    Schema<ChangeData> schema = index.getSchema();
     return schema.hasField(def);
   }