Intent to Ship: DEAA (Antialiasing) for CSS Transformed Layer Edges for the OpenGL Compositor (OSX and Linux)

[Kearwood "Kip" Gilbert]

As of April 24, 2015 I intent to turn on by default DEAA (Antialiasing)
for CSS transformed layer edges on OSX. It has been developed behind
the layers.deaa.enabled preference.

Platform coverage:
This will be enabled for all desktop platforms that use the OpenGL
compositor back-end. Currently, OSX is the only desktop platform with
the OpenGL compositor back-end enabled by default. Once the OpenGL
compositor is enabled for Linux with Bug 594876, DEAA will become active
on Linux as well.

Mobile platforms will be enabled later, potentially through a white-list
system that will be populated with specific devices that meet
performance and compatibility criteria.

This feature was previously discussed in this "intent to implement" thread:

https://groups.google.com/d/msg/mozilla.dev.platform/XPCp_8iFxgM/paSHh-t4qyYJ

Bugs to turn on by default:

https://bugzilla.mozilla.org/show_bug.cgi?id=1152977 (OSX)
https://bugzilla.mozilla.org/show_bug.cgi?id=1152974 (Linux)

Link to standard:

This feature does not change any API's and takes effect automatically
for existing web content. Other browsers have already shipped with this
enabled, using a similar DEAA implementation.

- Kearwood "Kip" Gilbert