fix crash in okular - I am not sure why this didn't happen before (the fix comes from msdn http://msdn.microsoft.com/en-us/library/aa366589.aspx - look at the example)

svn path=/branches/KDE/4.2/kdegraphics/okular/; revision=923029

core/document.cpp

@@ -249,7 +249,7 @@ qulonglong DocumentPrivate::getTotalMemory()
     }
 #elif defined(Q_OS_WIN)
     MEMORYSTATUSEX stat;
-
+    stat.dwLength = sizeof(stat);
     GlobalMemoryStatusEx (&stat);
 
     return ( cachedValue = stat.ullTotalPhys );
@@ -295,7 +295,7 @@ qulonglong DocumentPrivate::getFreeMemory()
     return ( cachedValue = (Q_UINT64_C(1024) * memoryFree) );
 #elif defined(Q_OS_WIN)
     MEMORYSTATUSEX stat;
-
+    stat.dwLength = sizeof(stat);
     GlobalMemoryStatusEx (&stat);
 
     lastUpdate = QTime::currentTime();