Metal: Upstream uniform limits from WebKit Increases the limit from 4k to 16k which matches OpenGL. Patches are from: https://bugs.webkit.org/show_bug.cgi?id=238914 https://bugs.webkit.org/show_bug.cgi?id=240896 Bug: angleproject:7280 Change-Id: I404adce0066680513e3eaa56bd4b1079c39a7f03 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3669602 Commit-Queue: Gregg Tavares <gman@chromium.org> Reviewed-by: Kenneth Russell <kbr@chromium.org>