Ignore failures in fontmgr_iter angle/gpu GM tests on Windows

expectations/gm/Test-Win7-ShuttleA-HD2000-x86-Debug-ANGLE/expected-results.json

Index: expectations/gm/Test-Win7-ShuttleA-HD2000-x86-Debug-ANGLE/expected-results.json
===================================================================
--- expectations/gm/Test-Win7-ShuttleA-HD2000-x86-Debug-ANGLE/expected-results.json	(revision 11105)
+++ expectations/gm/Test-Win7-ShuttleA-HD2000-x86-Debug-ANGLE/expected-results.json	(working copy)
@@ -7700,8 +7700,9 @@
         ]
       ], 
       "bugs": [
-        1578
+        1597
       ], 
+      "ignore-failure": true, 
       "reviewed-by-human": false
     }, 
     "fontmgr_iter_factory_565.png": {
@@ -7760,8 +7761,9 @@
         ]
       ], 
       "bugs": [
-        1578
+        1597
       ], 
+      "ignore-failure": true, 
       "reviewed-by-human": false
     }, 
     "fontmgr_match_565.png": {