pt 1 in reviving the android build (copied from pm 28a1, wish me luck)

mobile/android/thirdparty/com/squareup/picasso/Callback.java

@@ -0,0 +1,31 @@
+/*
+ * Copyright (C) 2013 Square, Inc.
+ *
+ * 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.squareup.picasso;
+
+public interface Callback {
+  void onSuccess();
+
+  void onError();
+
+  public static class EmptyCallback implements Callback {
+
+    @Override public void onSuccess() {
+    }
+
+    @Override public void onError() {
+    }
+  }
+}