add tool generated whitespace

the rebaseline tool adds whitespace at the end of lines in the json file.
While harmless, git flags this as something worth fixing. Fixing it causes
the rebaseline tool to generate a new difference with the whitespace.

Checking the whitespace back in to avoid future back-and-forth.

TBR=
NOTRY=true
NOTREECHECKS=true

Author: caryclark@google.com

Review URL: https://codereview.chromium.org/494363002

expectations/gm/Test-Ubuntu12-ShuttleA-GTX660-x86-Release/expected-results.json

@@ -6988,8 +6988,8 @@
       ], 
       "bugs": [
         2826
-      ],
-      "ignore-failure": true,
+      ], 
+      "ignore-failure": true, 
       "reviewed-by-human": true
     }, 
     "degeneratesegments_pdf-poppler.png": {