Support serialization of Mockito mocks

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I'm writing a unit-test for Android app, which creates a mock of serializable custom class and tries to serialize it. It works fine in JUnit test when I'm running it in JVM, but fails with following error when I'm running it as Android test in emulator:

[Full gist of error message](https://gist.github.com/rsharifu/71a377e1c0c0ad293852c722df7cb729).
```
W/System.err: java.io.NotSerializableException: com.android.dx.mockito.InvocationHandlerAdapter
W/System.err: at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1224)
W/System.err: at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1584)
W/System.err: at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1549)
W/System.err: at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1472)
```

Here is my code ([Android test gist](https://gist.github.com/rsharifu/db4948525075b0a1e85d2087d2cb0441)):
```
Entity serializableMock = mock(Entity.class, Mockito.withSettings().serializable());
try {
ObjectOutputStream out = new ObjectOutputStream(new ByteArrayOutputStream());
out.writeObject(serializableMock);
} catch (IOException e) {//catching NotSerializableException here}
```

Entity:
```
package org.test;
public class Entity implements Serializable {
public String str;
// getters/setters
}
```

Gradle dependencies:
```
androidTestCompile 'org.mockito:mockito-core:2.4.0'
androidTestCompile 'com.linkedin.dexmaker:dexmaker-mockito:2.2.0'
androidTestCompile "com.android.support:support-annotations:25.0.0"
androidTestCompile 'com.android.support.test:runner:0.5'
androidTestCompile 'com.android.support.test:rules:0.5'
```

How to properly serialize mock object on Android?

Reproduce the Android emulator test from the issue using the shown Mockito serializable mock and inspect the com.android.dx.mockito.InvocationHandlerAdapter failure. Trace how the Android mock handler participates in ObjectOutputStream serialization. Done means the provided Entity mock can be serialized in an Android test without NotSerializableException.

Written by the indexing model from the issue text.