richedit: do not read actual scrollbar state for scrollbar update, use internal state instead

[Alex Villací­s Lasso]

Alex Villací­s Lasso escribió:
> This is supposed to be a fix for bug #12311 . This bug involves a 
> recursive message loop where the application forces visibility of 
> scrollbars for the richedit control, which causes a WM_SIZE that 
> triggers an update of the window size and re-hiding of the scrollbar. 
> However, just after exiting the richedit winproc, the app forces 
> visibility again, which again triggers a WM_SIZE, and so on. Native is 
> oblivious to the fact that an external agent is messing with the 
> scrollbar visibility, and is therefore unaffected by recursion. This 
> patch attempts to fix this behavior in builtin and test for it. I have 
> tried to test it on WinXP-SP2 and Win98, but testing on other 
> platforms is helpful too.
>
> Changelog:
> * Use internal copy of scrollbar state instead of directly reading 
> state from scrollbars, just as native does.
> * Tests for ability to externally modify scrollbars.
> * Test for behavior that caused recursion until builtin richedit was 
> fixed.
>
> ------------------------------------------------------------------------
>
Nobody has commented on this patch. Is this the wrong strategy to solve 
the problem? Or are tests failing in some other platform? Copy of patch 
at bug #12311 with downloadable app to test.


-- 
perl -e '$x=2.4;print sprintf("%.0f + %.0f = %.0f\n",$x,$x,$x+$x);'