Remove old change screen

The following code was removed:

UI:

  * ChangeScreen (1)
  * SideBySide (1)
  * NewChangeScreenBar

Database columns in the accounts table:

  * change_screen
  * reverse_patch_set_order
  * comment_visibility_strategy

Change-Id: I7ec4a0beb51dd6cb2f7c364df40e7cb5bea786d2

gerrit-server/src/main/java/com/google/gerrit/server/schema/SchemaVersion.java

@@ -32,7 +32,7 @@ import java.util.List;
 /** A version of the database schema. */
 public abstract class SchemaVersion {
   /** The current schema version. */
-  public static final Class<Schema_103> C = Schema_103.class;
+  public static final Class<Schema_104> C = Schema_104.class;
 
   public static int getBinaryVersion() {
     return guessVersion(C);

gerrit-server/src/main/java/com/google/gerrit/server/schema/Schema_104.java

@@ -0,0 +1,27 @@
+// Copyright (C) 2015 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.schema;
+
+import com.google.inject.Inject;
+import com.google.inject.Provider;
+
+public class Schema_104 extends SchemaVersion {
+  @Inject
+  Schema_104(Provider<Schema_103> prior) {
+    super(prior);
+  }
+
+  // Remove old change screen
+}