Reduce the number of TextureFormatCaps members. Since GL has no notion of texture formats that can be used for different types of textures, merge the TextureFormatCaps texture support members. Also merge the various renderability members since the texture type is enough to determine what type of renderable a format is. BUG=angle:658 Change-Id: I7cba50b147fcca8f3880d65c06c57df9c65ed19c Reviewed-on: https://chromium-review.googlesource.com/206830 Reviewed-by: Jamie Madill <jmadill@chromium.org> Tested-by: Geoff Lang <geofflang@chromium.org>