Remove use of "use_mirror" recipe property.

scripts/slave/recipe_modules/perf_dashboard/example.expected/mac.json

Index: scripts/slave/recipe_modules/perf_dashboard/example.expected/mac.json
diff --git a/scripts/slave/recipe_modules/perf_dashboard/example.expected/mac.json b/scripts/slave/recipe_modules/perf_dashboard/example.expected/mac.json
index 0f1bb2e5efb5b7aff219936443d58fc9b84d18fd..c629b632871a6f67837c72cc43f4b19138c17c2f 100644
--- a/scripts/slave/recipe_modules/perf_dashboard/example.expected/mac.json
+++ b/scripts/slave/recipe_modules/perf_dashboard/example.expected/mac.json
@@ -6,9 +6,9 @@
       "RECIPE_MODULE[build::perf_dashboard]/resources/post_json.py"
     ],
     "name": "perf dashboard post",
-    "stdin": "{\"data\": [{\"bot\": \"multivm-windows-perf-be\", \"buildername\": \"multivm-windows-perf-be\", \"buildnumber\": 75, \"error\": \"0.5\", \"master\": \"client.dart.fyi\", \"masterid\": \"client.dart.fyi\", \"revision\": 33241, \"supplemental_columns\": {\"r_webkit_rev\": \"167808\"}, \"test\": \"sunspider/string-unpack-code/ref\", \"units\": \"ms\", \"value\": \"18.5\"}, {\"bot\": \"multivm-windows-perf-be\", \"buildername\": \"multivm-windows-perf-be\", \"buildnumber\": 75, \"error\": \"0.4898\", \"master\": \"client.dart.fyi\", \"masterid\": \"client.dart.fyi\", \"revision\": 33241, \"supplemental_columns\": {\"r_webkit_rev\": \"167808\"}, \"test\": \"sunspider/string-unpack-code\", \"units\": \"ms\", \"value\": \"18.4\"}], \"url\": \"https://chrome-perf.googleplex.com/add_point\"}",
+    "stdin": "{\"data\": [{\"bot\": \"multivm-windows-perf-be\", \"buildername\": \"multivm-windows-perf-be\", \"buildnumber\": 75, \"error\": \"0.5\", \"master\": \"client.dart.fyi\", \"masterid\": \"client.dart.fyi\", \"revision\": 33241, \"supplemental_columns\": {\"r_webkit_rev\": \"167808\"}, \"test\": \"sunspider/string-unpack-code/ref\", \"units\": \"ms\", \"value\": \"18.5\"}, {\"bot\": \"multivm-windows-perf-be\", \"buildername\": \"multivm-windows-perf-be\", \"buildnumber\": 75, \"error\": \"0.4898\", \"master\": \"client.dart.fyi\", \"masterid\": \"client.dart.fyi\", \"revision\": 33241, \"supplemental_columns\": {\"r_webkit_rev\": \"167808\"}, \"test\": \"sunspider/string-unpack-code\", \"units\": \"ms\", \"value\": \"18.4\"}], \"url\": \"https://chromeperf.appspot.com/add_point\"}",
     "~followup_annotations": [
-      "@@@STEP_LINK@Results Dashboard@https://chrome-perf.googleplex.com/report?rev=33241&masters=client.dart.fyi&tests=sunspider%2Fstring-unpack-code&bots=bot_name@@@"
+      "@@@STEP_LINK@Results Dashboard@https://chromeperf.appspot.com/report?rev=33241&masters=client.dart.fyi&tests=sunspider%2Fstring-unpack-code&bots=bot_name@@@"
     ]
   },
   {
@@ -18,7 +18,7 @@
       "RECIPE_MODULE[build::perf_dashboard]/resources/post_json.py"
     ],
     "name": "Post bisect results",
-    "stdin": "{\"data\": {\"status\": \"completed\", \"try_job_id\": 1}, \"url\": \"https://chrome-perf.googleplex.com/post_bisect_results\"}",
+    "stdin": "{\"data\": {\"status\": \"completed\", \"try_job_id\": 1}, \"url\": \"https://chromeperf.appspot.com/post_bisect_results\"}",
     "stdout": "/path/to/tmp/json",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@json.output@{@@@",