Bug 1277055 - Bump Firefox UI test results to Tier-2 on Treeherder. r=garndt

MozReview-Commit-ID: DJZQfCuySHl

--HG--
extra : rebase_source : 0f1b05062ee3a75f4bdafd63cebf8e0dc6a24414

testing/taskcluster/tasks/tests/fx_linux64_firefox_ui_functional.yml

@@ -24,4 +24,4 @@ task:
       groupName: Desktop firefox-ui-tests
       groupSymbol: tc-Fxfn
       symbol: en-US
-      tier: 3
+      tier: 2

testing/taskcluster/tasks/tests/fx_linux64_firefox_ui_functional_e10s.yml

@@ -25,4 +25,4 @@ task:
       groupName: Desktop firefox-ui-tests
       groupSymbol: tc-Fxfn-e10s
       symbol: en-US
-      tier: 3
+      tier: 2