add crashtest for bug 893523 using testcase by jruderman@gmail.com

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extra : transplant_source : %C9y%C9%A3%DF%BF%01%E6%A25%D4%C4%28G%FE%FF%94%2B%E9%D5
b=893523 clamp CSS pixel to nscoord conversion to nscoord_MIN,MAX r=roc

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extra : transplant_source : P%87%C2l%86%9AWu%CD%06%E5%22%D3%88/%80a%CE%80p
b=900337 Document that nsIThreadPool::Shutdown() will run the event loop  r=ehsan

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extra : transplant_source : %93%D8%96%C2%3A%60%7E%B9%96U%CC%C0%21e%A6%D2%BD%DD%E3-