Rebaseline minor pixel diffs from recent GPU changes.

expectations/gm/Test-Win8-ShuttleA-GTX660-x86-Release/expected-results.json

 {
   "expected-results": {
     "3x3bitmaprect_565.png": {
       "allowed-digests": [
         [
           "bitmap-64bitMD5", 
           12831071530564277917
         ]
       ], 
       "bugs": [
@@ skipping 4480 matching lines @@
       ], 
       "bugs": [
         1935
       ], 
       "reviewed-by-human": false
     }, 
     "canvas-state_nvprmsaa4.png": {
       "allowed-digests": [
         [
           "bitmap-64bitMD5", 
-          5541967782360980927
+          17407313805298369905
         ]
       ], 
       "reviewed-by-human": true
     }, 
     "canvas-state_pdf-poppler.png": {
       "allowed-digests": [
         [
           "bitmap-64bitMD5", 
           2093000810176756252
         ]
@@ skipping 14342 matching lines @@
           14019814087375927425
         ]
       ], 
       "bugs": [
         1935
       ], 
       "reviewed-by-human": false
     }
   }
 }