gradtext also needed rebaselining from the gamma change

expectations/gm/Test-ChromeOS-Link-HD4000-x86_64-Debug/expected-results.json

 {
   "expected-results": {
     "3x3bitmaprect_565.png": {
       "allowed-digests": [
         [
           "bitmap-64bitMD5", 
           12831071530564277917
         ]
       ], 
       "bugs": [
@@ skipping 3945 matching lines @@
           "bitmap-64bitMD5", 
           5025305727406958156
         ]
       ], 
       "reviewed-by-human": true
     }, 
     "gradtext_8888.png": {
       "allowed-digests": [
         [
           "bitmap-64bitMD5", 
-          1624698241546705458
+          15612462860180208512
         ]
       ], 
       "reviewed-by-human": true
     }, 
     "hairlines_565.png": {
       "allowed-digests": [
         [
           "bitmap-64bitMD5", 
           9293293797458777202
         ]
@@ skipping 2638 matching lines @@
           2149562185397201955
         ]
       ], 
       "bugs": [
         1578
       ], 
       "reviewed-by-human": false
     }
   }
 }