Add tests for OES_texture_buffer
This MR adds tests for the extension OES_texture_buffer. They are mostly ports from the ARB_texture_buffer_object and ARB_texture_buffer_range, updating the shaders and removing the stuff not supported on OpenGL ES.
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This MR adds tests for the extension OES_texture_buffer. They are mostly ports from the ARB_texture_buffer_object and ARB_texture_buffer_range, updating the shaders and removing the stuff not supported on OpenGL ES.