Files app: Handle chrome.runtime.lastError for chrome.storage API calls.

ui/file_manager/file_manager/common/js/util.js

Index: ui/file_manager/file_manager/common/js/util.js
diff --git a/ui/file_manager/file_manager/common/js/util.js b/ui/file_manager/file_manager/common/js/util.js
index 1f0a9de1a534e4f9123d7d8fb118bb12f7c30557..f5a0455729d33f3a55142f9127cdaa790a276f56 100644
--- a/ui/file_manager/file_manager/common/js/util.js
+++ b/ui/file_manager/file_manager/common/js/util.js
@@ -387,7 +387,11 @@ util.saveAppState = function() {
   var items = {};
 
   items[window.appID] = JSON.stringify(window.appState);
-  chrome.storage.local.set(items);
+  chrome.storage.local.set(items, function() {
+    if (chrome.runtime.lastError)
+      console.error('Failed to save app state: ' +
+          chrome.runtime.lastError.message);
+  });
 };
 
 /**