Readding null checks for the set of extensions returned by GetInstalledExtensions.

BUG=404187

Review URL: https://codereview.chromium.org/478753002

Cr-Commit-Position: refs/heads/master@{#290031}
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@290031 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/metrics/extensions_metrics_provider.cc

@@ -193,6 +193,8 @@ void ExtensionsMetricsProvider::ProvideOffStoreMetric(
 
     scoped_ptr<extensions::ExtensionSet> extensions(
         GetInstalledExtensions(profiles[i]));
+    if (!extensions)
+      continue;
 
     // Combine the state from each profile, always favoring the higher state as
     // defined by the order of ExtensionState.
@@ -212,6 +214,8 @@ void ExtensionsMetricsProvider::ProvideOccupiedBucketMetric(
 
   scoped_ptr<extensions::ExtensionSet> extensions(
       GetInstalledExtensions(profile));
+  if (!extensions)
+    return;
 
   const int client_key = GetClientID() % kExtensionListClientKeys;