[UXTHEME] Add a hack for themed scrollbars

- After inspecting a theme file with different upper or lower tracks it seems that windows use what is called LowerTrackHorz and LowerTrackVert in the upper track and UpperTrackHorz and  UpperTrackVert are used in the lower track.
CORE-13513

Author: yagoulas

dll/win32/uxtheme/ncscrollbar.c

@@ -215,16 +215,18 @@ static void SCROLL_DrawInterior( PDRAW_CONTEXT pcontext, SCROLLBARINFO* psbi,
         return;
     }
 
+    /* Some themes have different bitmaps for the upper and lower tracks  
+       It seems that windows use the bitmap for the lower track in the upper track */
     if (vertical)
     { 
         rcPart = r;
         rcPart.bottom = thumbPos;
-        SCROLL_ThemeDrawPart(pcontext, SBP_UPPERTRACKVERT, BUTTON_NORMAL, psbi, SCROLL_TOP_RECT, htDown, htHot, &rcPart);
+        SCROLL_ThemeDrawPart(pcontext, SBP_LOWERTRACKVERT, BUTTON_NORMAL, psbi, SCROLL_TOP_RECT, htDown, htHot, &rcPart);
         r.top = rcPart.bottom;
 
         rcPart = r;
         rcPart.top += psbi->xyThumbBottom - psbi->xyThumbTop;
-        SCROLL_ThemeDrawPart(pcontext, SBP_LOWERTRACKVERT, BUTTON_NORMAL, psbi, SCROLL_BOTTOM_RECT, htDown, htHot, &rcPart); 
+        SCROLL_ThemeDrawPart(pcontext, SBP_UPPERTRACKVERT, BUTTON_NORMAL, psbi, SCROLL_BOTTOM_RECT, htDown, htHot, &rcPart); 
         r.bottom = rcPart.top;
 
         SCROLL_ThemeDrawPart(pcontext, SBP_THUMBBTNVERT, BUTTON_NORMAL, psbi, SCROLL_THUMB, htDown, htHot, &r); 
@@ -234,12 +236,12 @@ static void SCROLL_DrawInterior( PDRAW_CONTEXT pcontext, SCROLLBARINFO* psbi,
     {
         rcPart = r;
         rcPart.right = thumbPos;
-        SCROLL_ThemeDrawPart(pcontext, SBP_UPPERTRACKHORZ, BUTTON_NORMAL, psbi, SCROLL_TOP_RECT, htDown, htHot, &rcPart);
+        SCROLL_ThemeDrawPart(pcontext, SBP_LOWERTRACKHORZ, BUTTON_NORMAL, psbi, SCROLL_TOP_RECT, htDown, htHot, &rcPart);
         r.left = rcPart.right;
 
         rcPart = r;
         rcPart.left += psbi->xyThumbBottom - psbi->xyThumbTop;
-        SCROLL_ThemeDrawPart(pcontext, SBP_LOWERTRACKHORZ, BUTTON_NORMAL, psbi, SCROLL_BOTTOM_RECT, htDown, htHot, &rcPart);
+        SCROLL_ThemeDrawPart(pcontext, SBP_UPPERTRACKHORZ, BUTTON_NORMAL, psbi, SCROLL_BOTTOM_RECT, htDown, htHot, &rcPart);
         r.right = rcPart.left;
 
         SCROLL_ThemeDrawPart(pcontext, SBP_THUMBBTNHORZ, BUTTON_NORMAL, psbi, SCROLL_THUMB, htDown, htHot, &r);