gradtext also needed rebaselining from the gamma change

expectations/gm/Test-Mac10.8-MacMini4.1-GeForce320M-x86_64-Release/expected-results.json

 {
   "actual-results": {
     "failed": null, 
     "failure-ignored": null, 
     "no-comparison": null, 
     "succeeded": null
   }, 
   "expected-results": {
     "3x3bitmaprect_565.png": {
       "allowed-digests": [
@@ skipping 10070 matching lines @@
           "bitmap-64bitMD5", 
           1196992559341551804
         ]
       ], 
       "reviewed-by-human": true
     }, 
     "gradtext_8888.png": {
       "allowed-digests": [
         [
           "bitmap-64bitMD5", 
-          11700296070969547344
+          11341488244958220268
         ]
       ], 
       "reviewed-by-human": true
     }, 
     "gradtext_gpu.png": {
       "allowed-digests": [
         [
           "bitmap-64bitMD5", 
-          15344723582785809200
+          6426034390838459732
         ]
       ], 
       "reviewed-by-human": true
     }, 
     "gradtext_pdf-mac.png": {
       "allowed-digests": [
         [
           "bitmap-64bitMD5", 
           13425337007731220089
         ]
@@ skipping 6903 matching lines @@
           7829854837061118142
         ]
       ], 
       "bugs": [
         1578
       ], 
       "reviewed-by-human": false
     }
   }
 }