Win32: Fix monitor event emission

Fixes #784.

README.md

@@ -166,6 +166,7 @@ information on what to include when reporting a bug.
 - [Win32] Bugfix: The 32-bit Vulkan loader library static was not searched for
 - [Win32] Bugfix: Vulkan libraries have a new path as of SDK 1.0.42.0 (#956)
 - [Win32] Bugfix: Monitors with no display devices were not enumerated (#960)
+- [Win32] Bugfix: Monitor events were not emitted (#784)
 - [X11] Replaced `_GLFW_HAS_XF86VM` compile-time option with dynamic loading
 - [X11] Bugfix: `glfwGetVideoMode` would segfault on Cygwin/X
 - [X11] Bugfix: Dynamic X11 library loading did not use full sonames (#941)

src/win32_init.c

@@ -307,10 +307,10 @@ static HWND createHelperWindow(void)
     MSG msg;
     HWND window = CreateWindowExW(WS_EX_OVERLAPPEDWINDOW,
                                   _GLFW_WNDCLASSNAME,
-                                  L"GLFW helper window",
+                                  L"GLFW message window",
                                   WS_CLIPSIBLINGS | WS_CLIPCHILDREN,
                                   0, 0, 1, 1,
-                                  HWND_MESSAGE, NULL,
+                                  NULL, NULL,
                                   GetModuleHandleW(NULL),
                                   NULL);
     if (!window)

src/win32_window.c

@@ -467,14 +467,13 @@ static LRESULT CALLBACK windowProc(HWND hWnd, UINT uMsg,
 
         switch (uMsg)
         {
+            case WM_DISPLAYCHANGE:
+                _glfwPollMonitorsWin32();
+                break;
+
             case WM_DEVICECHANGE:
             {
-                if (wParam == DBT_DEVNODES_CHANGED)
+                if (wParam == DBT_DEVICEARRIVAL)
-                {
-                    _glfwPollMonitorsWin32();
-                    return TRUE;
-                }
-                else if (wParam == DBT_DEVICEARRIVAL)
                 {
                     DEV_BROADCAST_HDR* dbh = (DEV_BROADCAST_HDR*) lParam;
                     if (dbh)