x11: Split out conditions and warnings

XGetGeometry is a great piece of API, since it gets a lot of stuff that
are moderately *not* geometry related - the root window, and the depth
being two.

Since we have multiple conditions depending on the result of that call
we should split them up depending on the actual error - and each of them
should have a separate error message. This makes debugging simpler.

clutter/x11/clutter-stage-x11.c

@@ -905,12 +905,26 @@ clutter_x11_set_stage_foreign (ClutterStage *stage,
                          &border,
                          &depth);
 
-  if (clutter_x11_untrap_x_errors () ||
+  if (clutter_x11_untrap_x_errors () || !status)
-      !status ||
-      width == 0 || height == 0 ||
-      depth != xvisinfo->depth)
     {
-      g_warning ("Unable to retrieve the new window geometry");
+      g_critical ("Unable to retrieve the geometry of the foreign window: "
+                  "XGetGeometry() failed (status code: %d)", status);
+      return FALSE;
+    }
+
+  if (width == 0 || height == 0)
+    {
+      g_warning ("The size of the foreign window is 0x0");
+      return FALSE;
+    }
+
+  if (depth != xvisinfo->depth)
+    {
+      g_warning ("The depth of the visual of the foreign window is %d, but "
+                 "Clutter has been initialized to require a visual depth "
+                 "of %d",
+                 depth,
+                 xvisinfo->depth);
       return FALSE;
     }