EXT_float_blend is core in ES 3.2
EXT_float_blend is core in ES 3.2

Bug: angleproject:5098
Change-Id: I084defba9dd83153a9b8d2ee83f7d50e82eb154c
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2430164
Reviewed-by: Shrek Shao <7ae796039b2f0529765a6c4b0ab8ce931d949d23@google.com>
Reviewed-by: Jonah Ryan-Davis <682bdb9e7d8ba359ef169b8db374e7a99d394a46@google.com>
Commit-Queue: Jonah Ryan-Davis <682bdb9e7d8ba359ef169b8db374e7a99d394a46@google.com>

ppy/angle,ppy/angle,ppy/angle,ppy/angle