Avoid retaining a reference to ActivityIconLoader in its OnIconReady()

components/arc/intent_helper/activity_icon_loader.cc

Index: components/arc/intent_helper/activity_icon_loader.cc
diff --git a/components/arc/intent_helper/activity_icon_loader.cc b/components/arc/intent_helper/activity_icon_loader.cc
index d83b6a1da1bca4c3641d31da24959ae96be20d1b..b4f0c097f8011301d314c1b038de195a80ab17aa 100644
--- a/components/arc/intent_helper/activity_icon_loader.cc
+++ b/components/arc/intent_helper/activity_icon_loader.cc
@@ -163,8 +163,8 @@ void ActivityIconLoader::OnIconsReady(
   ArcServiceManager* manager = ArcServiceManager::Get();
   base::PostTaskAndReplyWithResult(
       manager->blocking_task_runner().get(), FROM_HERE,
-      base::Bind(&ActivityIconLoader::ResizeAndEncodeIcons, this,
-                 base::Passed(&icons)),
+      base::Bind(&ActivityIconLoader::ResizeAndEncodeIcons,

[hidehiko, 2017/01/26 13:14:20]

(I know it is not your mistake, but ...)

ResizeAndEncodeIcons can be static. So could you mark as static and remove
"this" from here, instead?

thread_checker_ DCHECK looks wrong check, because this instance is created on
the browser thread, while the method should run on a BlockingPool thread, so
could you remove it?

You can keep the field, because we still want to check the thread where other
methods run. So, as you're here, could you add

DCHECK(thread_checker_.CalledOnValidThread()); 

to the beginning of the following methods?
- InvalidateIcons()
- GetActivityIcons()
- OnIconsReady() and
- OnIconsResized().

[tzik, 2017/01/26 13:21:12]

Done.

+                 base::Unretained(this), base::Passed(&icons)),
       base::Bind(&ActivityIconLoader::OnIconsResized, this,
                  base::Passed(&cached_result), cb));
 }