Give Chrome Web Store app an icon in its manifest file.

chrome/renderer/extensions/resource_request_policy.cc

Index: chrome/renderer/extensions/resource_request_policy.cc
diff --git a/chrome/renderer/extensions/resource_request_policy.cc b/chrome/renderer/extensions/resource_request_policy.cc
index c9973c8a5d075f6e235407b6010c8454e147883a..da83a32643ee9ef5b7be9ffa5f9e56910a383878 100644
--- a/chrome/renderer/extensions/resource_request_policy.cc
+++ b/chrome/renderer/extensions/resource_request_policy.cc
@@ -70,9 +70,12 @@ bool ResourceRequestPolicy::CanRequestResource(
         !extension->devtools_url().is_empty();
     bool transition_allowed =
         !content::PageTransitionIsWebTriggerable(transition_type);
+    // - unreachable web page error page (to allow showing the icon of the
+    //   unreachable app on this page)
+    bool is_error_page = frame_url == GURL(content::kUnreachableWebDataURL);
 
     if (!is_empty_origin && !is_own_resource &&
-        !is_dev_tools && !transition_allowed) {
+        !is_dev_tools && !transition_allowed && !is_error_page) {
       std::string message = base::StringPrintf(
           "Denying load of %s. Resources must be listed in the "
           "web_accessible_resources manifest key in order to be loaded by "