gdiplus: Implement GdipSetCustomLineCapWidthScale.

dlls/gdiplus/customlinecap.c

@@ -221,17 +221,16 @@ GpStatus WINGDIPAPI GdipSetCustomLineCapStrokeJoin(GpCustomLineCap* custom,
     return Ok;
 }
 
-GpStatus WINGDIPAPI GdipSetCustomLineCapWidthScale(GpCustomLineCap* custom,
-    REAL width)
+GpStatus WINGDIPAPI GdipSetCustomLineCapWidthScale(GpCustomLineCap* custom, REAL width)
 {
-    static int calls;
-
     TRACE("(%p,%0.2f)\n", custom, width);
 
-    if(!(calls++))
-        FIXME("not implemented\n");
+    if(!custom)
+        return InvalidParameter;
 
-    return NotImplemented;
+    custom->scale = width;
+
+    return Ok;
 }
 
 GpStatus WINGDIPAPI GdipGetCustomLineCapBaseCap(GpCustomLineCap *customCap, GpLineCap *baseCap)