Bug 1662347 - Rename `Renderer::gpu_profile` as `gpu_profiler`. r=gw
Bug 1662347 - Rename `Renderer::gpu_profile` as `gpu_profiler`. r=gw

Because the underlying type is called `GpuProfiler`, and there is *also* a
separate type `GpuProfile`, so the current name is misleading.

Differential Revision: https://phabricator.services.mozilla.com/D88954

[ghsync] From https://hg.mozilla.org/mozilla-central/rev/d08ac41c61a712c6826e4bd1ae7bcc06a53d5c5c

servo/webrender,servo/webrender,servo/webrender,servo/webrender,servo/webrender,servo/webrender