Expand simultaneous XFB binding test

[lexaknyazev]

When a bufferData call is rejected due to simultaneous bindings, the bound buffer size must not reset. The new test fails in Chromium, passes in WebKit and Firefox.

[kenrussell]

Was there an associated WebKit bug fix for this new test? I haven't run the new test yet but it looks like on all platforms which use ANGLE this error should be caught:

https://source.chromium.org/chromium/chromium/src/+/main:third_party/angle/src/libANGLE/validationES2.cpp;l=3570?q=validationES2.cpp

[lexaknyazev]

WebKit was failing the test even before this PR; fixed here: https://commits.webkit.org/253210@main.

Chromium resets the buffer size before calling into ANGLE:
https://source.chromium.org/chromium/chromium/src/+/main:third_party/blink/renderer/modules/webgl/webgl_rendering_context_base.cc;l=2171

[kenrussell]

Upon further review, I see the Chromium-side cache that's being updated incorrectly during this test and am fixing it; would still appreciate pointers to any WebKit bug fixes. Thanks.