[//gpu] Remove CrashOnInProcessANGLEContextLoss feature

We have not been able to get useful data from the experiment on this
feature, as there were extremely few clients in the experiment. We are
not planning on reviving it imminently, so remove it. The code can
always be brought back if needed.

Bug: 40264184
Change-Id: I29a29918249d85c1cb50ce46decc331684d520f2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5314383
Reviewed-by: Vasiliy Telezhnikov <vasilyt@chromium.org>
Commit-Queue: Colin Blundell <blundell@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1263984}