Some more medium/MIP downsample gpu rebaslines and misc gpu innocuous rebaselines

expectations/gm/Test-Android-Nexus7-Tegra3-Arm7-Debug/expected-results.json

 {
   "actual-results": {
     "failed": null, 
     "failure-ignored": null, 
     "no-comparison": null, 
     "succeeded": null
   }, 
   "expected-results": {
     "3x3bitmaprect_565.png": {
       "allowed-digests": [
@@ skipping 3163 matching lines @@
       ], 
       "bugs": [
         1578
       ], 
       "reviewed-by-human": false
     }, 
     "downsamplebitmap_checkerboard_medium_512_256_gpu.png": {
       "allowed-digests": [
         [
           "bitmap-64bitMD5", 
-          8916009523280789816
+          10440183167364399689
         ]
       ], 
-      "bugs": [
-        1578
-      ], 
-      "reviewed-by-human": false
+      "reviewed-by-human": true
     }, 
     "downsamplebitmap_checkerboard_none_512_256_565.png": {
       "allowed-digests": [
         [
           "bitmap-64bitMD5", 
           3646964297203490771
         ]
       ], 
       "bugs": [
         1578
@@ skipping 4726 matching lines @@
       "allowed-digests": [
         [
           "bitmap-64bitMD5", 
           9347373815292268764
         ]
       ], 
       "ignore-failure": false
     }
   }
 }