Where is the default app source code remains in Android 2.2 source code?

I have downloaded the Source code of Android 2.2 . Where can I find the default app source code of Android (Calculator,开发者_StackOverflow中文版 Calendar, etc, on pressing Home Button)

I found Calculator,Calender and some other android app source code in this page: http://grepcode.com/file/repository.grepcode.com/java/ext/com.google.android/android-apps/2.3_r1/com/android/calculator2/Calculator.java/

looking at this you should be able to find it:

https://android.googlesource.com

For example, digging through following the links I found Calculator source code in Froyo:

https://android.googlesource.com/platform/packages/apps/Calculator/+/froyo-release/src/com/android/calculator2/Calculator.java

The system Apps are available in (folder path): packages/apps/Calculator/ , packages/apps/Calendar/

For more details check: http://androidxref.com/