Converting WebGLObject from EagerSweeping to PreFinalizers

Replaced WebGLObject's RunDestructor method with a PreFinalize method.
Removed destructors from all classes inheriting from WebGLObject.
PreFinalizer relies on the same virtual methods as the previous
destructor.

Measured performance using tough_webgl stories of rendering.desktop
benchmark. No significant regressions observed.
Summary of results regarding PreFinalization performance:
https://docs.google.com/spreadsheets/d/1vXjVxS5jFT2Bxla8wKzbCXVgUFvKC86WN0vgt0XK8KE/edit?usp=sharing

Bug: 981043
Change-Id: I1ff2762a843c4c443fd0c2f948484a46a0e94738
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1690834
Commit-Queue: Omer Katz <omerkatz@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Kenneth Russell <kbr@chromium.org>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Cr-Commit-Position: refs/heads/master@{#676616}
14 files changed