build(deps): bump glow from 0.10.0 to 0.11.0

[dependabot]

Bumps glow from 0.10.0 to 0.11.0.

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[iceiix]

error[E0277]: the trait bound `NativeTexture: std::default::Default` is not satisfied
   --> src/gl/mod.rs:263:20
    |
263 | pub struct Texture(glow::Texture);
    |                    ^^^^^^^^^^^^^ the trait `std::default::Default` is not implemented for `NativeTexture`
    |
    = note: required by `std::default::Default::default`
    = note: this error originates in the derive macro `Default` (in Nightly builds, run with -Z macro-backtrace for more info)

lots of errors of this form, for each of the glow structures. How were they changed? Looks like it can be tracked down to this commit: grovesNL/glow@e6c11f7 (Use newtypes for native GL handles) from grovesNL/glow#180. Glow is now using the newtype pattern much the same as I am in src/gl/mod.rs:

#[derive(Copy, Clone, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
 pub struct NativeShader(NonZeroU32);

but is #[derive(Default)] actually needed, is it used anywhere? Only one place:

impl Drop for VertexArray {
    fn drop(&mut self) {
        unsafe {
            glow_context().delete_vertex_array(self.0);
        }
        self.0 = glow::VertexArray::default();
    }
}

intending to zero-out the released resource, to not leave it dangling. However the new glow::NativeVertexArray is now a newtype of std::num::NonZeroU32: https://doc.rust-lang.org/std/num/struct.NonZeroU32.html

An integer that is known not to equal zero.

This enables some memory layout optimization. For example, Option is the same size as u32:

The intent, I believe, is for safety. But impl Drop for FrameBuffer and Texture do not zero on delete. If I really need to denote this value as freed or not present, it may be better typed as an Option<glow::VertexArray>. Trying removing the assignment first, no ill effects observed so far.

[iceiix]

Removing the defaults works on my local machine, but fails in CI because it causes new clippy warnings - probably the reason I added these defaults in the first place:

warning: you should consider adding a `Default` implementation for `gl::Framebuffer`
   --> src/gl/mod.rs:852:5
    |
852 | /     pub fn new() -> Framebuffer {
853 | |         Framebuffer(unsafe {
854 | |             glow_context()
855 | |                 .create_framebuffer()
856 | |                 .expect("create framebuffer failed")
857 | |         })
858 | |     }
    | |_____^
    |
    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#new_without_default
help: try this
    |
851 | impl Default for gl::Framebuffer {
852 |     fn default() -> Self {
853 |         Self::new()
854 |     }
855 | }
    |