Just include the GL headers from cpp files only, since it can conflict between epoxy, angle and system headers.
Pull request: https://github.com/WebKit/WebKit/pull/20983
Grouping the includes in a single header is not the problem, it just makes easier to make a mistake and include the common header from another header. For example, in angle we have ANGLEHeaders.h and it's not a problem as long as it's only included from cpp files and not unified with others, see the comment in the header: // Note: this file can't be compiled in the same unified source file // as others which include the system's OpenGL headers. I can keep the common header if you prefer, but we need to make sure it's never included in headers and cpp files including it are not unified.
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