rebaseline downsample_text and downsample_checkerboard GMs on gpu configs

expectations/gm/Test-Mac10.6-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 4884 matching lines @@
       ], 
       "bugs": [
         1578
       ], 
       "reviewed-by-human": false
     }, 
     "downsamplebitmap_checkerboard_high_512_256_gpu.png": {
       "allowed-digests": [
         [
           "bitmap-64bitMD5", 
-          6481939352948074473
+          17528203856946988833
         ]
       ], 
-      "bugs": [
-        1578
-      ], 
-      "reviewed-by-human": false
+      "reviewed-by-human": true
     }, 
     "downsamplebitmap_checkerboard_high_512_256_pdf-mac.png": {
       "allowed-digests": [
         [
           "bitmap-64bitMD5", 
           16093357615070406962
         ]
       ], 
       "bugs": [
         1578
@@ skipping 402 matching lines @@
       ], 
       "bugs": [
         1578
       ], 
       "reviewed-by-human": false
     }, 
     "downsamplebitmap_text_high_72.00pt_gpu.png": {
       "allowed-digests": [
         [
           "bitmap-64bitMD5", 
-          14843072844415365931
+          4745997174382078910
         ]
       ], 
-      "bugs": [
-        1578
-      ], 
-      "reviewed-by-human": false
+      "reviewed-by-human": true
     }, 
     "downsamplebitmap_text_high_72.00pt_pdf-mac.png": {
       "allowed-digests": [
         [
           "bitmap-64bitMD5", 
           10111800974903191139
         ]
       ], 
       "bugs": [
         1578
@@ skipping 7752 matching lines @@
           7829854837061118142
         ]
       ], 
       "bugs": [
         1578
       ], 
       "reviewed-by-human": false
     }
   }
 }