Notify Files App when ARC++ app is installed/removed

chrome/browser/chromeos/extensions/file_manager/event_router.cc

Index: chrome/browser/chromeos/extensions/file_manager/event_router.cc
diff --git a/chrome/browser/chromeos/extensions/file_manager/event_router.cc b/chrome/browser/chromeos/extensions/file_manager/event_router.cc
index 2b78461c5a07ff58cbacdfa590ab0b40537a8eae..832e0efae6fc3674425242077ab9c687903fc803 100644
--- a/chrome/browser/chromeos/extensions/file_manager/event_router.cc
+++ b/chrome/browser/chromeos/extensions/file_manager/event_router.cc
@@ -37,6 +37,7 @@
 #include "chromeos/login/login_state.h"
 #include "chromeos/network/network_handler.h"
 #include "chromeos/network/network_state_handler.h"
+#include "components/arc/intent_helper/arc_intent_helper_bridge.h"

[Yusuke Sato, 2016/11/17 02:29:54]

nit: Remove. You can rely on the header file in this case.

https://google.github.io/styleguide/cppguide.html#Names_and_Order_of_Includes
reads "However, any includes present in the related header do not need to be
included again in the related cc (i.e., foo.cc can rely on foo.h's includes)."

[oka, 2016/11/21 07:02:15]

Done.

 #include "components/drive/chromeos/file_system_interface.h"
 #include "components/drive/drive_pref_names.h"
 #include "components/drive/file_change.h"
@@ -400,6 +401,14 @@ EventRouter::EventRouter(Profile* profile)
 EventRouter::~EventRouter() {
 }
 
+void EventRouter::OnAppsUpdated() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  BroadcastEvent(profile_,
+                 extensions::events::FILE_MANAGER_PRIVATE_ON_APPS_UPDATED,
+                 file_manager_private::OnAppsUpdated::kEventName,
+                 file_manager_private::OnAppsUpdated::Create());
+}
+
 void EventRouter::Shutdown() {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
   chromeos::system::TimezoneSettings::GetInstance()->RemoveObserver(this);
@@ -492,6 +501,10 @@ void EventRouter::ObserveEvents() {
   pref_change_registrar_->Add(prefs::kUse24HourClock, callback);
 
   chromeos::system::TimezoneSettings::GetInstance()->AddObserver(this);
+
+  arc::ArcIntentHelperBridge* bridge = arc::ArcIntentHelperBridge::Get();
+  DCHECK(bridge);

[kinaba, 2016/11/17 01:47:19]

When ARC is not enabled (either by config or when the device does not support it
at all),
|bridge| may be null, IIUC.

[Yusuke Sato, 2016/11/17 02:29:54]

Yeah, and you might have to retry later to avoid introducing a race. I'll
comment more on this later.

[Yusuke Sato, 2016/11/17 04:22:37]

Sorry I misread your code. ArcIntentHelperBridge instance is created in
ChromeBrowserMainPartsChromeos::PreMainMessageLoopRun() regardless of whether
ARC is supported or not, so you code doesn't seem to have a race.

hidehiko:
Can |bridge| be nullptr here? I don't remember if ArcServiceManager's Shutdown()
is actually called on production code.

[hidehiko, 2016/11/17 07:34:19]

I think no. In past, the launcher creation was guarded by a flag IIRC, but
nowadays it is created always. I'm not sure it is ensured in all test cases,
though.
It is.
https://cs.chromium.org/chromium/src/chrome/browser/chromeos/chrome_browser_m...

Note that the Shutdown is called before the BrowserContextKeyedService is
destructed.

[Yusuke Sato, 2016/11/17 09:15:27]

Got it, thanks for refreshing my memory.

+  bridge->AddObserver(this);

[Yusuke Sato, 2016/11/17 02:29:54]

AddObserver should almost always be paired with RemoveObserver. For other
observer interfaces, EventRouter::Shutdown() seems to call RemoveObserver in the
reverse order. Shouldn't we do that too?

[oka, 2016/11/21 07:02:15]

Done.

 }
 
 // File watch setup routines.