Remove warnings for zero-sized structs
This change removes a bunch of warnings from the crate.
The only remaining warnings are due to the bitflags macro usage.
This will help fixservo/core-text-rs#62 when it upgrades to `core-graphics = 0.9`.
@jdm
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Introduces CGWindowList API for window capturing and improves `CGImage` and `CGContext`
Initially I just wanted to rewrite https://github.com/servo/core-graphics-rs/pull/52 as it seems that the author is not interested in changing his pull request. So I just implemented `CGImage` bindings, but today another pull request has been merged (https://github.com/servo/core-graphics-rs/pull/79) which does exactly the same.
This pull request still improves some things in regards to `CGImage`, the most important ones are:
* Now `CGImage` uses `CGImageRelease` instead of `CFRelease` (it's a much safer to use `CGImageRelease` here, as it does not crash if you pass a `NULL` image reference to it).
* Now you can retrieve bytes from `CGImage` (uses data provider and copies the bytes from it).
Also several improvements in `CGContext`:
* Added a function `create_image()`, which allows you to create an image out of existing `CGContext`.
* Now it is possible to specify a data pointer passed as a first parameter to the `CGBitmapContextCreate()` upon `CGContext` creation -- very important thing when you deal with images as it allows you to specify your own buffer instead of allocating and copying an additional one from the context (tested it on my machine, it gave me 18.46% of performance boost).
And of course this pull requests adds `CGWindowListCreateImage()` and related things, so now window capturing is possible.
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Add CGEvent and CGEventSource
Added CGEvent and CGEventSource to simulate keyboard events.
FFI corresponds mostly to their respective headers in CoreGraphics except for some data types which are defined in CGEventTypes.h.
Uses:
CoreGraphics.framework/Headers/CGEvent.h
CoreGraphics.framework/Headers/CGEventSource.h
CoreGraphics.framework/Headers/CGEventTypes.h
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Kornel
