stop after at most 200 iterations in WalkFrom() to avoid looping endlessly when the stack is corrupted (patch 1759239)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_2_8_BRANCH@47767 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/msw/stackwalk.cpp

@@ -266,8 +266,9 @@ void wxStackWalker::WalkFrom(const CONTEXT *pCtx, size_t skip)
     #error "Need to initialize STACKFRAME on non x86"
 #endif // _M_IX86
 
-    // iterate over all stack frames
-    for ( size_t nLevel = 0; ; nLevel++ )
+    // iterate over all stack frames (but stop after 200 to avoid entering
+    // infinite loop if the stack is corrupted)
+    for ( size_t nLevel = 0; nLevel < 200; nLevel++ )
     {
         // get the next stack frame
         if ( !wxDbgHelpDLL::StackWalk