remove suppression as all GMs have been rebased or were uneffected.

Review URL: https://codereview.chromium.org/807653003
diff --git a/expectations/gm/ignored-tests.txt b/expectations/gm/ignored-tests.txt
index 8b6106b..6574096 100644
--- a/expectations/gm/ignored-tests.txt
+++ b/expectations/gm/ignored-tests.txt
@@ -42,7 +42,3 @@
 
 #humper skia:2049
 dashcubics
-
-#derekf
-drawbitmapmatrix
-