Fixed bug 2496 - mouse left button double click event issue

cplu

When I double click on a window, the "clicks" field (newly added since 2.0.2) in SDL_MouseButtonEvent is 1 instead of 2.
However, when I "tripple" click, "clicks" field is then 2.
I'v look into the source code in SDL_windowsevents.c and found that when a double click event comes, WIN_WindowProc will get a WM_LBUTTONDBLCLK msg. The message sequence of a double click is:WM_LBUTTONDOWN->WM_LBUTTONUP->WM_LBUTTONDBLCLK->WM_LBUTTONUP.

src/video/windows/SDL_windowsevents.c

@@ -407,9 +407,13 @@ WIN_WindowProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
     case WM_MBUTTONUP:
     case WM_XBUTTONUP:
     case WM_LBUTTONDOWN:
+    case WM_LBUTTONDBLCLK:
     case WM_RBUTTONDOWN:
+    case WM_RBUTTONDBLCLK:
     case WM_MBUTTONDOWN:
+    case WM_MBUTTONDBLCLK:
     case WM_XBUTTONDOWN:
+    case WM_XBUTTONDBLCLK:
         {
             SDL_Mouse *mouse = SDL_GetMouse();
             if (!mouse->relative_mode || mouse->relative_mode_warp) {