user32/tests: Release window DCs consistently.

dlls/user32/tests/cursoricon.c

@@ -1070,6 +1070,8 @@ static void test_LoadImageBitmap(const char * test_desc, HBITMAP hbm)
     ok(ret == bm.bmHeight, "%s: %d lines were converted, not %d\n", test_desc, ret, bm.bmHeight);
 
     ok(color_match(pixel, 0x00ffffff), "%s: Pixel is 0x%08x\n", test_desc, pixel);
+
+    ReleaseDC(NULL, hdc);
 }
 
 static void test_LoadImageFile(const char * test_desc, const unsigned char * image_data,

dlls/user32/tests/static.c

@@ -99,6 +99,7 @@ static void test_updates(int style, int flags)
         HDC hdc = GetDC( hStatic);
         COLORREF colour = GetPixel( hdc, 10, 10);
         ok ( colour != 0, "pixel should NOT be painted black!\n");
+        ReleaseDC(hStatic, hdc);
     }
     if (style != SS_ETCHEDHORZ && style != SS_ETCHEDVERT)
         exp = 4;

dlls/user32/tests/sysparams.c

@@ -2918,7 +2918,8 @@ static void test_GetSystemMetrics( void)
         trace( "Captionfontchar width %d  MenuFont %d,%d CaptionWidth from registry: %d screen %d,%d\n",
                 avcwCaption, tmMenuFont.tmHeight, tmMenuFont.tmExternalLeading, CaptionWidthfromreg, screen.cx, screen.cy);
     }
-    ReleaseDC( 0, hdc);
+
+    DeleteDC(hdc);
 }
 
 static void test_EnumDisplaySettings(void)

dlls/user32/tests/win.c

@@ -5242,6 +5242,7 @@ static void test_scrolldc( HWND parent)
     if (winetest_debug > 0) dump_region(hrgn);
 
     /* clean up */
+    ReleaseDC(hwnd1, hdc);
     DeleteObject(hrgn);
     DeleteObject(exprgn);
     DeleteObject(tmprgn);