Enable new session crashed bubble UI by Finch experiment.

chrome/browser/ui/startup/startup_browser_creator_impl.cc

Index: chrome/browser/ui/startup/startup_browser_creator_impl.cc
diff --git a/chrome/browser/ui/startup/startup_browser_creator_impl.cc b/chrome/browser/ui/startup/startup_browser_creator_impl.cc
index 9ea079f53d99aac2954565d3968c24ca1fd45c72..bff9ad326db18499f8eabb067c42f1263fffdcfd 100644
--- a/chrome/browser/ui/startup/startup_browser_creator_impl.cc
+++ b/chrome/browser/ui/startup/startup_browser_creator_impl.cc
@@ -16,6 +16,7 @@
 #include "base/environment.h"
 #include "base/lazy_instance.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/metrics/field_trial.h"
 #include "base/metrics/histogram.h"
 #include "base/metrics/statistics_recorder.h"
 #include "base/path_service.h"
@@ -129,6 +130,11 @@ enum LaunchMode {
   LM_LINUX_MAC_BEOS           // Other OS buckets start here.
 };
 
+// The Finch experiment name and group name that enables new bubble UI after
+// session crashes.
+const char kManagedModeFinchName[] = "EnalbeSessionCrashedBubbleUI";
+const char kEnalbeBubbleUIGroupEnabled[] = "Enabled";
+
 #if defined(OS_WIN)
 // Undocumented flag in the startup info structure tells us what shortcut was
 // used to launch the browser. See http://www.catch22.net/tuts/undoc01 for
@@ -845,8 +851,11 @@ void StartupBrowserCreatorImpl::AddInfoBarsIfNecessary(
     return;
 
   if (HasPendingUncleanExit(browser->profile())) {
-    if (!command_line_.HasSwitch(switches::kEnableSessionCrashedBubble) ||
-        !ShowSessionCrashedBubble(browser))
+    // The new bubble UI can be enabled by Finch experiment or by flag.
+    if (!((base::FieldTrialList::FindFullName(kManagedModeFinchName) ==
+               kEnalbeBubbleUIGroupEnabled ||
+           command_line_.HasSwitch(switches::kEnableSessionCrashedBubble)) &&
+          ShowSessionCrashedBubble(browser)))

[Alexei Svitkine (slow), 2014/05/15 19:02:35]

Hmm, I think it would be better to move this logic to
ShowSessionCrashedBubble(), given that we have a single implementation of it.

That way, we won't put users into the active Finch group if they're running a
version of Chrome that doesn't support it.

I think you should also add a --disable flag, so that when the behaviour is
enabled via Finch, one can both turn it on or off explicitly.

(Move both the flag handling and the Finch check into the function.)

[yao, 2014/05/15 21:19:38]

Done.

       SessionCrashedInfoBarDelegate::Create(browser);
   }