Among the announcements at Google I/O was news about the next version of Android. Dubbed as Android L (since Android 4.4 was Android K, as in KitKat) the new version is currently available as a developer preview. Google made preview images available for some Nexus devices, and now the search giant has started integrating some of the code from Android L into the Android Open Source Project (AOSP)
When Android 4.0.4 was released, the then AOSP Technical Lead – Jean-Baptiste Queru, published a quick script that creates a basic changelog from one release of AOSP to the next. The script still works and Funky Android has released a changelog between Android 4.4.2 and Android L-preview.
The log only shows the changes available via the Android Open Source Project and does not include any changes in any proprietary components included by Google or any hardware manufacturer. Google’s commits to the AOSP are not yet complete and won’t be until Android L is finally released. It seems that the Android L-preview release was forked from the 4.4 code base shortly after Android 4.4.2 was committed.
There are over 400 commits which relate to the 64-bit ARM architecture.
There are two versions of the changelog available, the one linked above does not include any of the changes made to Chromium. For a full list of AOSP changes including the Chromium changes, please see this log.
A quick analysis of the changelog shows that there are over 400 commits which relate to the 64-bit ARM architecture (commonly known as AArch64 or ARMv8). There are another 300 or so that are connected with Intel’s 64 bit architecture (or x86_64).
There are some 1500 changes from Android 4.4 to Android L just in the ART sub-project alone.
Google is also continuing its development of ART, the next generation of Java virtual machine which will likely become the default VM for Android L. There are some 1500 changes from Android 4.4 to Android L just in the ART sub-project alone. However Dalvik hasn’t been completely ignored by Google, there are over 120 modifications to Dalvik in Android-L since Android 4.4.
Funky Android also has other changelogs available, including the differences between the various minor point releases of AOSP (like 4.4.3 from 4.4.2), as well as the changelogs from AOSP 4.1 to 4.2, 4.2 to 4.3, 4.3 to 4.4. You can see the full lists on the Android Open Source Project Changelogs page.