new file mode 100644
--- /dev/null
+++ b/toolkit/components/telemetry/tests/unit/test_TelemetryFlagClear.js
@@ -0,0 +1,17 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+const Cu = Components.utils;
+const {Services} = Cu.import("resource://gre/modules/Services.jsm", {});
+
+function run_test()
+{
+  let testFlag = Services.telemetry.getHistogramById("TELEMETRY_TEST_FLAG");
+  equal(JSON.stringify(testFlag.snapshot().counts), "[1,0,0]", "Original value is correct");
+  testFlag.add(1);
+  equal(JSON.stringify(testFlag.snapshot().counts), "[0,1,0]", "Value is correct after ping.");
+  testFlag.clear();
+  equal(JSON.stringify(testFlag.snapshot().counts), "[1,0,0]", "Value is correct after calling clear()");
+  testFlag.add(1);
+  equal(JSON.stringify(testFlag.snapshot().counts), "[0,1,0]", "Value is correct after ping.");
+}

--- a/toolkit/components/telemetry/tests/unit/xpcshell.ini
+++ b/toolkit/components/telemetry/tests/unit/xpcshell.ini
@@ -1,14 +1,15 @@
 [DEFAULT]
 head = head.js
 tail = 
 skip-if = toolkit == 'gonk'
 
 [test_nsITelemetry.js]
+[test_TelemetryFlagClear.js]
 [test_TelemetryLateWrites.js]
 [test_TelemetryLockCount.js]
 [test_TelemetryLog.js]
 [test_TelemetryPing.js]
 # Bug 676989: test fails consistently on Android
 # fail-if = os == "android"
 [test_TelemetryPing_idle.js]
 [test_TelemetryStopwatch.js]