Building latest ADB from AOSP source code

[Tao_2019]

Hi,
I am trying to build the adb from latest AOSP source code tree, and I retrieved the latest AOSP source code from master branch, which I found here: https://android.googlesource.com/platform/manifest/+refs. The download and building went well, but I could only got adb at version 28.0.2, which is different from the latest adb version at 29.0.5, from here: https://developer.android.com/studio/releases/platform-tools.
So my question is: Is 28.0.2 is the most stable release of adb which recommended by Google? or I need to modify some files (such as some version control file) to make it building latest adb (29.0.5 for now) ?

 

[Tao_2019]

To answer my own question, in case somebody get caught at the same place.
after remove previous leftover .repo folder under my building directory, and run "repo init -u https://android.googlesource.com/platform/manifest" again, to create new .repo folder, I can get the real master branch code and build latest adb (for now it's 29.0.5).