gdi32/tests: Avoid variable length arrays (MSVC).

dlls/gdi32/tests/bitmap.c

@@ -1588,7 +1588,7 @@ static BOOL is_black_pen( COLORREF fg, COLORREF bg, int r, int g, int b )
 static void test_bitmap_colors( HDC hdc, COLORREF fg, COLORREF bg, int r, int g, int b )
 {
     static const WORD pattern_bits[] = { 0x5555, 0xaaaa, 0x5555, 0xaaaa, 0x5555, 0xaaaa, 0x5555, 0xaaaa };
-    char buffer[FIELD_OFFSET( BITMAPINFO, bmiColors[256] )];
+    char buffer[FIELD_OFFSET( BITMAPINFO, bmiColors ) + 256 * sizeof(RGBQUAD)];
     BITMAPINFO *info = (BITMAPINFO *)buffer;
     RGBQUAD *colors = info->bmiColors;
     WORD bits[16];

dlls/gdi32/tests/pen.c

@@ -512,7 +512,7 @@ static void test_ps_userstyle(void)
     LOGBRUSH lb;
     HPEN pen;
     INT size, i;
-    char buffer[offsetof(EXTLOGPEN, elpStyleEntry[16])];
+    char buffer[offsetof(EXTLOGPEN, elpStyleEntry) + 16 * sizeof(DWORD)];
     EXTLOGPEN *ext_pen = (EXTLOGPEN *)buffer;
 
     lb.lbColor = 0x00ff0000;
@@ -569,7 +569,7 @@ static void test_ps_userstyle(void)
 
 static void test_brush_pens(void)
 {
-    char buffer[offsetof(EXTLOGPEN, elpStyleEntry[16])];
+    char buffer[offsetof(EXTLOGPEN, elpStyleEntry) + 16 * sizeof(DWORD)];
     EXTLOGPEN *elp = (EXTLOGPEN *)buffer;
     LOGBRUSH lb;
     HPEN pen = 0;