Fail Vulkan surface creation if window has context

OpenGL / OpenGL ES cannot share presentation on a window with Vulkan.
This adds an error to `glfwCreateWindowSurface` when it is called on a
window without the GLFW_CLIENT_API hint set to GLFW_NO_API.  This
prevents undefined bahevior and hard to debug crashes.

Fixes #1194.
Closes #1205.

src/vulkan.c

@@ -317,6 +317,13 @@ GLFWAPI VkResult glfwCreateWindowSurface(VkInstance instance,
         return VK_ERROR_EXTENSION_NOT_PRESENT;
     }
 
+    if (window->context.client != GLFW_NO_API)
+    {
+        _glfwInputError(GLFW_INVALID_VALUE,
+                        "Vulkan: Window surface creation requires the window to have the client API set to GLFW_NO_API");
+        return VK_ERROR_NATIVE_WINDOW_IN_USE_KHR;
+    }
+
     return _glfwPlatformCreateWindowSurface(instance, window, allocator, surface);
 }