This happens when you have 3 projects in your eclipse dev environment.
1) Library project : here you have common stuff between other projects
2) Android project : here you have your android app, which has the Library project as a project in your build path
3) Android Test Instrumentation project : here you have your test cases which run on your android device.
Naturally you will include 1 and 2 as dependent projects to 3, in 3’s properties->java build path -> projects.
Instead you need to edit the project properties on 2. On 2, Properties->JavaBuildPath->OrderandExport, check the Library project for exporting.
Dont include the library project into 3, instead just include 2 in 3. Since 1 is exported in 2, you will be ok. And this error will go away.
I referred to this blog for this issue.