* Make all structs readonly when applicable. It should reduce amount of needless defensive copies
* Make structs with trivial boilerplate equality code record structs
* Remove unnecessary readonly modifiers from TextureCreateInfo
* Make BitMap structs readonly too
* Do not allow render targets not explicitly written by the fragment shader to be modified
* Shader cache version bump
* Remove blank lines
* Avoid redundant color mask updates
* HostShaderCacheEntry can be null
* Avoid more redundant glColorMask calls
* nit: Mask -> Masks
* Fix currentComponentMask
* More efficient way to update _currentComponentMasks
