Version:  refs/heads/master@{#402737}
OS: Windows 10

What steps will reproduce the problem?
(1) open http://vmiura.github.io/svg-anim/svg-anim.html?ldddd,tiger
(2) open web inspector
(3) observe the printed FPS number degrade

What is the expected output?
The FPS number stays the same

What do you see instead?
In 1-2 mins the number starts to drop.

No drop if either of the flags are omitted.

Please use labels and text to provide additional information.

It appears that there's some sort of resource leak on Windows when using --use-gl=desktop. 
I know the flag is not supported at the moment, but maybe this is still a sign 
that something is wrong? Or maybe 

Driver:10.18.13.6839
GL_VENDOR	NVIDIA Corporation
GL_RENDERER	GeForce GTX 1080/PCIe/SSE2
GL_VERSION	4.5.0 NVIDIA 368.39

Adding a trace when the page has slowed down. I did not find which call was the one slowing down. I don't know if I got the correct categories to trace in order to see the slowdown directly.

I'm investigating the --use-gl=desktop flag on Windows since when talking to kbr, there seemed to be a possibility to perhaps someday run Chrome Windows on GL, if the quality is there.
 

Deleted: trace_slow-use-gl-desktop-enable-gpu-rasterization.json.gz 1.6 MB

trace_slow-use-gl-desktop-enable-gpu-rasterization.json.gz 1.6 MB Download