Improve ephemeral profiles clean up code.

chrome/browser/chrome_browser_main.cc

Index: chrome/browser/chrome_browser_main.cc
diff --git a/chrome/browser/chrome_browser_main.cc b/chrome/browser/chrome_browser_main.cc
index 7c341da961a6d68209eac6a1441ad6aba9cca355..87425693948fb27f1334156efc65fbd235c0f76e 100644
--- a/chrome/browser/chrome_browser_main.cc
+++ b/chrome/browser/chrome_browser_main.cc
@@ -202,6 +202,8 @@ using content::BrowserThread;
 
 namespace {
 
+const int64 kEphemeralProfilesCleanUpDelaySec = 10;
+
 // This function provides some ways to test crash and assertion handling
 // behavior of the program.
 void HandleTestParameters(const CommandLine& command_line) {
@@ -1042,9 +1044,18 @@ void ChromeBrowserMainParts::PreProfileInit() {
     if (profile_cache.ProfileIsEphemeralAtIndex(i))
       profiles_to_delete.push_back(profile_cache.GetPathOfProfileAtIndex(i));
   }
-  for (size_t i = 0;i < profiles_to_delete.size(); ++i) {
-    profile_manager->ScheduleProfileForDeletion(
-        profiles_to_delete[i], ProfileManager::CreateCallback());
+
+  if (profiles_to_delete.size()) {
+    for (size_t i = 0;i < profiles_to_delete.size(); ++i) {
+      profile_manager->ScheduleProfileForDeletion(
+          profiles_to_delete[i], ProfileManager::CreateCallback());
+    }
+    // Clean up the profiles soon after browser start, but not immediately not
+    // to delay browser start-up.

[rpetterson, 2013/11/04 18:18:59]

Was there noticeable slow down for startup without the delay?

[pastarmovj, 2013/11/05 08:58:17]

To be honest I have never tried. Since I need to post the task to the FILE
thread anyways I thought I will also make it late enough to make sure no
start-up tasks are blocked on deleting potentially large amount of files.
Especially since Windows is known to be slow deleting many small files.

[jochen (gone - plz use gerrit), 2013/11/05 13:03:25]

I don't think we should do that, unless you have data to show that this actually
slows down startup, and delaying it by 10 seconds does not.

[pastarmovj, 2013/11/05 16:11:02]

After discussing this with Jochen. I can see the point of not waiting here until
we gather evidence that this is indeed needed.

+    BrowserThread::PostDelayedTask(
+        BrowserThread::FILE, FROM_HERE,
+        base::Bind(&ProfileManager::CleanUpStaleProfiles, profiles_to_delete),
+        base::TimeDelta::FromSeconds(kEphemeralProfilesCleanUpDelaySec));
   }
 #endif  // OS_ANDROID