Refactor ActivityStatus to not store current activity

base/android/application_state_list.h

Index: base/android/application_state_list.h
diff --git a/base/android/application_state_list.h b/base/android/application_state_list.h
new file mode 100644
index 0000000000000000000000000000000000000000..6b74e3b1a41fca40994f5477a51455f64a1d147d
--- /dev/null
+++ b/base/android/application_state_list.h
@@ -0,0 +1,14 @@
+// Copyright (c) 2014 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.
+
+// This file intentionally does not have header guards, it's included
+// inside a macro to generate enum values.
+
+#ifndef DEFINE_APPLICATION_STATE
+#error "DEFINE_APPLICATION_STATE should be defined before including this file"
+#endif
+DEFINE_APPLICATION_STATE(RUNNING, 1)

[bulach, 2014/02/13 11:17:48]

see below, perhaps it'd be better to have something like:
HAS_ANY_RUNNING_ACTIVITIES
HAS_ONLY_PAUSED_ACTIVITIES
HAS_ONLY_STOPPED_ACTIVITIES
DESTROYED

to be more explicit this is not an application state per se, but rather a
derivation of the underlying activities? wdyt?

[David Trainor- moved to gerrit, 2014/02/14 19:13:36]

Done.

+DEFINE_APPLICATION_STATE(PAUSED, 2)
+DEFINE_APPLICATION_STATE(STOPPED, 3)
+DEFINE_APPLICATION_STATE(DESTROYED, 3)