Bug 505115 part 18 fixed this for the perspective() function, but not for the 'perspective' property.
Created attachment 595117 [details] [diff] [review] Patch Mochitests in layout/style/test/ all pass on my machine. Didn't push to tryservers because my account hasn't been created yet.
Autoland Patchset: Patches: 595117 Branch: mozilla-central => try Destination: http://hg.mozilla.org/try/rev/8472b2cb12d8 Try run started, revision 8472b2cb12d8. To cancel or monitor the job, see: https://tbpl.mozilla.org/?tree=Try&rev=8472b2cb12d8
Try run for 8472b2cb12d8 is complete. Detailed breakdown of the results available here: https://tbpl.mozilla.org/?tree=Try&rev=8472b2cb12d8 Results (out of 210 total builds): success: 183 warnings: 20 other: 7 Builds (or logs if builds failed) available at: http://email@example.com Timed out after 06 hours without completing.
All the failures look unrelated -- some are filed as intermittent failures, and some memory leaks on Win debug. And a timeout on Android opt C1.