Google has prepared a search and navigation system for Android code

Google company commissioned service cs.android.com, designed to search by code in git repositories associated with the Android platform. The search takes into account the various classes of elements found in the code, and the result is displayed in a visual form with syntax highlighting, the ability to cross-reference navigation and view the history of changes. For example, you can click on the name of a function in the code and go to the place where it is defined or see where else it is called. You can also switch between different branches and evaluate changes between them.

Source: opennet.ru