inital apk extension support

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branch : apk
Fixing issues discovered by Philipp Wiesemann

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branch : apk
access google apk library through reflection

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branch : apk
added comment

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branch : apk
Implemented SDL_CaptureMouse().
Implement SDL_CaptureMouse() for Mac OS X.
Flip this around to do the simpler condition first.
Added SDL_PointInRect().

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extra : amend_source : dda056b2033a9b6b370eefd66ac9653a5050a476
First shot at SDL_SetWindowDragAreas().

Only Cocoa implemented right now.

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extra : amend_source : b178ad0ae25b933b284ed1bda89df750ddd27fb3
Initial work on X11 implementation of SDL_SetWindowDragAreas().
Some updates for the X11 drag areas work.
Don't hardcode an 8 here.
Changed drag area API to a hit-testing API.

There were several good arguments for this: it's how Windows works with
 WM_NCHITTEST, SDL doesn't need to manage a list of rects, it allows more
 control over the regions (how do you use rects to cleanly surround a circular
 button?), the callback can be more optimized than a iterating a list of
 rects, and you don't have to send an updated list of rects whenever the
 window resizes or layout changes.

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rename : test/testdragareas.c => test/testhittesting.c
Added a few debug printf() calls.
Tweaked hit-testing documentation.

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extra : rebase_source : df2f9ccdddf408e5aaf7e788a1983ce8fef13d46
First shot (not even compiled) at Windows hit-testing support.

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extra : rebase_source : 0563e3a3584a43403b46a8e89477deba4c502430
Make some printf() calls into SDL_Log() so I can see them on Windows.  :)
Patched to compile on Visual Studio.
Fixed hit-testing on Windows.

Needed to convert from screen to client coords.
Fixed up SDL_CaptureMouse() on Windows to work like I expected.

This would have been a one-line patch to the documentation (specifying that
 captures only work as long as the left mouse button is pressed), but I didn't
 like that, so I got a little crazy about this instead.