make ignored-tests.txt specify full test name, not partial name

gm/tests/outputs/compared-against-empty-dir/output-expected/json-summary.txt

Index: gm/tests/outputs/compared-against-empty-dir/output-expected/json-summary.txt
diff --git a/gm/tests/outputs/compared-against-empty-dir/output-expected/json-summary.txt b/gm/tests/outputs/compared-against-empty-dir/output-expected/json-summary.txt
index f33ea9d8723a3e922ed1d6164f503ff621358fac..69d205098195e49449b9af05b4df993a1e8b54b8 100644
--- a/gm/tests/outputs/compared-against-empty-dir/output-expected/json-summary.txt
+++ b/gm/tests/outputs/compared-against-empty-dir/output-expected/json-summary.txt
@@ -4,18 +4,28 @@
       "failure-ignored" : null,
       "no-comparison" : {
          "565/selftest1.png" : [ "bitmap-64bitMD5", 12927999507540085554 ],
-         "8888/selftest1.png" : [ "bitmap-64bitMD5", 1209453360120438698 ]
+         "565/selftest2.png" : [ "bitmap-64bitMD5", 8863920166200910451 ],
+         "8888/selftest1.png" : [ "bitmap-64bitMD5", 1209453360120438698 ],
+         "8888/selftest2.png" : [ "bitmap-64bitMD5", 13451349865803053525 ]

[epoger, 2014/01/13 20:23:46]

As before, this test confirms: even though a subset of the tests were set to
ignore-failure, they ALL show up as no-comparison (no-comparison trumps
failure-ignored)

       },
       "succeeded" : null
    },
    "expected-results" : {
       "565/selftest1.png" : {
          "allowed-digests" : null,
+         "ignore-failure" : true
+      },
+      "565/selftest2.png" : {
+         "allowed-digests" : null,
          "ignore-failure" : false
       },
       "8888/selftest1.png" : {
          "allowed-digests" : null,
          "ignore-failure" : true
+      },
+      "8888/selftest2.png" : {
+         "allowed-digests" : null,
+         "ignore-failure" : false
       }
    }
 }