Update some flaky GMs to see if they stick.

expectations/gm/Test-Win7-ShuttleA-HD2000-x86_64-Debug/expected-results.json

 {
   "actual-results": {
     "failed": null, 
     "failure-ignored": null, 
     "no-comparison": null, 
     "succeeded": null
   }, 
   "expected-results": {
     "3x3bitmaprect_565.png": {
       "allowed-digests": [
@@ skipping 4803 matching lines @@
       ], 
       "bugs": [
         1578
       ], 
       "reviewed-by-human": false
     }, 
     "dftext_gpu.png": {
       "allowed-digests": [
         [
           "bitmap-64bitMD5", 
-          17943552053568158147
+          15350805613334511829
         ]
       ], 
       "reviewed-by-human": true
     }, 
     "discard_gpu.png": {
       "allowed-digests": [
         [
           "bitmap-64bitMD5", 
           11635187478196931850
         ]
@@ skipping 5376 matching lines @@
           "bitmap-64bitMD5", 
           1120308788076075072
         ]
       ], 
       "ignore-failure": false
     }, 
     "pathfill_gpu.png": {
       "allowed-digests": [
         [
           "bitmap-64bitMD5", 
-          3419577956526145213
+          8333353183563338389
         ]
       ], 
       "ignore-failure": false, 
       "reviewed-by-human": true
     }, 
     "pathfill_pdf-poppler.png": {
       "allowed-digests": [
         [
           "bitmap-64bitMD5", 
           1313008434183403262
@@ skipping 3537 matching lines @@
       "allowed-digests": [
         [
           "bitmap-64bitMD5", 
           12937422788648264516
         ]
       ], 
       "reviewed-by-human": true
     }
   }
 }