tests: Drop yield() helper function

Remaining use case was when we move the pointer.  This doesn't change
geometry so we can just use a wl_display_roundtrip() to make sure
we get the request to the server and receive the resulting events.

tests/button-test.c

@@ -36,7 +36,8 @@ TEST(simple_button_test)
 	assert(pointer->button == 0);
 	assert(pointer->state == 0);
 
-	move_pointer(client, 150, 150);
+	wl_test_move_pointer(client->test->wl_test, 150, 150);
+	wl_display_roundtrip(client->wl_display);
 	assert(pointer->x == 50);
 	assert(pointer->y == 50);
 

tests/event-test.c

@@ -56,7 +56,8 @@ check_pointer(struct client *client, int x, int y)
 static void
 check_pointer_move(struct client *client, int x, int y)
 {
-	move_pointer(client, x, y);
+	wl_test_move_pointer(client->test->wl_test, x, y);
+	wl_display_roundtrip(client->wl_display);
 	check_pointer(client, x, y);
 }
 

tests/weston-test-client-helper.c

@@ -40,29 +40,6 @@ surface_contains(struct surface *surface, int x, int y)
 	return x >= sx && y >= sy && x < sx + sw && y < sy + sh;
 }
 
-void
-yield(struct client *client)
-{
-	/*
-	 * FIXME: ugh! how do we ensure all events have finished
-	 * propagating to the client.  The calls to usleep seem to do a
-	 * pretty reasonable job... and without them, tests can fail
-	 * intermittently.
-	 */
-	usleep(0.02 * 1e6);
-	wl_display_flush(client->wl_display);
-	wl_display_roundtrip(client->wl_display);
-	usleep(0.02 * 1e6);
-}
-
-void
-move_pointer(struct client *client, int x, int y)
-{
-	wl_test_move_pointer(client->test->wl_test, x, y);
-
-	yield(client);
-}
-
 static void
 move_client_frame_handler(void *data, 
 			  struct wl_callback *callback, uint32_t time)

tests/weston-test-client-helper.h

@@ -96,12 +96,6 @@ client_create(int x, int y, int width, int height);
 int
 surface_contains(struct surface *surface, int x, int y);
 
-void
-yield(struct client *client);
-
-void
-move_pointer(struct client *client, int x, int y);
-
 void
 move_client(struct client *client, int x, int y);