Add blobshader GM baselines.

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

 {
   "expected-results": {
     "3x3bitmaprect_565.png": {
       "allowed-digests": [
         [
           "bitmap-64bitMD5", 
           12831071530564277917
         ]
       ], 
       "bugs": [
@@ skipping 6512 matching lines @@
     }, 
     "textblob_8888.png": {
       "allowed-digests": [
         [
           "bitmap-64bitMD5", 
           3499763660998801760
         ]
       ], 
       "reviewed-by-human": true
     }, 
+    "textblobshader_8888.png": {
+      "allowed-digests": [
+        [
+          "bitmap-64bitMD5", 
+          1623616166746686472
+        ]
+      ], 
+      "reviewed-by-human": true
+    }, 
     "texteffects_565.png": {
       "allowed-digests": [
         [
           "bitmap-64bitMD5", 
           14682576320942451880
         ]
       ], 
       "bugs": [
         1578
       ], 
@@ skipping 510 matching lines @@
           2149562185397201955
         ]
       ], 
       "bugs": [
         1578
       ], 
       "reviewed-by-human": false
     }
   }
 }