Preserve hosted apps' background contents across reload

chrome/browser/background_contents_service.cc

Index: chrome/browser/background_contents_service.cc
diff --git a/chrome/browser/background_contents_service.cc b/chrome/browser/background_contents_service.cc
index df6db030e7d882dd47126185a60f7a64774b60db..dd90c52385b69a61ca31e8d9764f9ad26cb114ab 100644
--- a/chrome/browser/background_contents_service.cc
+++ b/chrome/browser/background_contents_service.cc
@@ -113,10 +113,21 @@ void BackgroundContentsService::Observe(NotificationType type,
       DCHECK(IsTracked(Details<BackgroundContents>(details).ptr()));
       RegisterBackgroundContents(Details<BackgroundContents>(details).ptr());
       break;
-    case NotificationType::EXTENSION_UNLOADED:
-      ShutdownAssociatedBackgroundContents(
-          ASCIIToUTF16(
-              Details<UnloadedExtensionInfo>(details)->extension->id()));
+   case NotificationType::EXTENSION_UNLOADED:
+      switch (Details<UnloadedExtensionInfo>(details)->reason) {
+        case UnloadedExtensionInfo::DISABLE:  // Intentionally fall through.
+        case UnloadedExtensionInfo::UNINSTALL:
+          ShutdownAssociatedBackgroundContents(
+              ASCIIToUTF16(
+                  Details<UnloadedExtensionInfo>(details)->extension->id()));
+            break;
+        case UnloadedExtensionInfo::UPDATE:
+           // Leave BackgroundContents in place
+           break;
+        default:
+           NOTREACHED();

[asargent_no_longer_on_chrome, 2011/01/15 00:09:53]

Would it make sense to shut down the background contents in the default case
here? I'm thinking of the possibility that in the future someone adds a new
reason type to UnloadedExtensionInfo and forgets to update your code here. I.e.
in release builds, where the NOTREACHED won't fire, would we rather err on the
side of the background contents getting shut down than left running? Your call -
just raising it for you to think about. 

[The wrong rickcam account, 2011/01/18 20:08:50]

Done.  I inserted a call to ShutdownAssociatedBackgroundContents immediately
following the NOTREACHED().

+           break;
+      }
       break;
     default:
       NOTREACHED();