clients: Implement minimum size for toy toolkit clients

We default to setting the minimum size to the initial size.  To set a
different minimum size than the initial size, set the minimum size first
then then initial size.  Good enough for a toy toolkit.

https://bugs.freedesktop.org/show_bug.cgi?id=50263
diff --git a/clients/terminal.c b/clients/terminal.c
index a726232..7e7a9fb 100644
--- a/clients/terminal.c
+++ b/clients/terminal.c
@@ -695,10 +695,6 @@
 	struct rectangle allocation;
 	struct winsize ws;
 
-	if (width < 1)
-		width = 1;
-	if (height < 1)
-		height = 1;
 	if (terminal->width == width && terminal->height == height)
 		return;
 
@@ -764,12 +760,6 @@
 	struct terminal *terminal = data;
 	int32_t columns, rows, m;
 
-    if (width < 200)
-        width = 200;
-
-    if (height < 50)
-        height = 50;
-
 	m = 2 * terminal->margin;
 	columns = (width - m) / (int32_t) terminal->extents.max_x_advance;
 	rows = (height - m) / (int32_t) terminal->extents.height;
@@ -2492,6 +2482,7 @@
 	cairo_destroy(cr);
 	cairo_surface_destroy(surface);
 
+	terminal_resize(terminal, 20, 5); /* Set minimum size first */
 	terminal_resize(terminal, 80, 25);
 
 	wl_list_insert(terminal_list.prev, &terminal->link);