EGL: Resource IDs for Surface, Context and EGL Image. This will make these classes play nicely with resource maps. As these objects are used in a lot of places, and simplified C can't handle unordered_map, it's necessary to index the maps by simple packed IDs in capture/replay code. This indirection will also have increased safety as we validate EGL resource ID handle values before accessing the memory directly. Also hides some of the other EGL capture methods behind helper methods to simplify the C code and hide assignments and other complex maps. Bug: angleproject:7758 Change-Id: Ibc7bb56430d3068bd38877c9dfb011979d4ea234 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3957164 Reviewed-by: Cody Northrop <cnorthrop@google.com> Commit-Queue: Jamie Madill <jmadill@chromium.org> Reviewed-by: Yuxin Hu <yuxinhu@google.com>