Some OpenGL ES 3.0 devices don't advertise OES_texture_half_float, but
do advertise EXT_color_buffer_half_float. For this reason, stop
requiring OES_texture_half_float when determining renderability of
GL_RGBA16F textures.
Bug: angleproject:4649
Change-Id: I657011fcc3bb35909760a57e8ad53cfbbc61c67a
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2212434Reviewed-by: Geoff Lang <geofflang@chromium.org>
Commit-Queue: Kenneth Russell <kbr@chromium.org>
