Perform alarm's period limit check while reading alarm info from StateStore.

extensions/browser/api/alarms/alarms_api_constants.cc

Index: extensions/browser/api/alarms/alarms_api_constants.cc
diff --git a/extensions/browser/api/alarms/alarms_api_constants.cc b/extensions/browser/api/alarms/alarms_api_constants.cc
new file mode 100644
index 0000000000000000000000000000000000000000..fbefff47b5433a91852799040c8da599ccf24544
--- /dev/null
+++ b/extensions/browser/api/alarms/alarms_api_constants.cc
@@ -0,0 +1,34 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "extensions/browser/api/alarms/alarms_api_constants.h"
+
+namespace extensions {
+namespace alarms_api_constants {
+
+// 0.016667 minutes  ~= 1s.
+const double kDevDelayMinimum = 0.016667;
+
+const int kReleaseDelayMinimum = 1;
+
+const char kWarningMinimumDevDelay[] =
+    "Alarm delay is less than minimum of 1 minutes. In released .crx, alarm "
+    "\"*\" will fire in approximately 1 minutes.";
+
+const char kWarningMinimumReleaseDelay[] =
+    "Alarm delay is less than minimum of 1 minutes. Alarm \"*\" will fire in "
+    "approximately 1 minutes.";
+
+const char kWarningMinimumDevPeriod[] =
+    "Alarm period is less than minimum of 1 minutes. In released .crx, alarm "
+    "\"*\" will fire approximately every 1 minutes.";
+
+const char kWarningMinimumReleasePeriod[] =
+    "Alarm period is less than minimum of 1 minutes. Alarm \"*\" will fire "
+    "approximately every 1 minutes.";
+
+static_assert(kReleaseDelayMinimum == 1, "warning message must be updated");
+
+}  // namespace alarms_api_constants
+}  // namespace extensions