Handles path absence instead of CHECKing.

chrome/browser/extensions/external_pref_extension_loader.cc

Index: chrome/browser/extensions/external_pref_extension_loader.cc
diff --git a/chrome/browser/extensions/external_pref_extension_loader.cc b/chrome/browser/extensions/external_pref_extension_loader.cc
index fc84b1ebf6df8b9023c67fba18696c0fd0069688..0d246b01c50735cfaca21b472616272377238262 100644
--- a/chrome/browser/extensions/external_pref_extension_loader.cc
+++ b/chrome/browser/extensions/external_pref_extension_loader.cc
@@ -60,19 +60,22 @@ void ExternalPrefExtensionLoader::StartLoading() {
 void ExternalPrefExtensionLoader::LoadOnFileThread() {
   CHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
 
-  CHECK(PathService::Get(base_path_key_, &base_path_));
+  scoped_ptr<DictionaryValue> prefs;
 
-  FilePath json_file;
-  json_file = base_path_.Append(FILE_PATH_LITERAL("external_extensions.json"));
+  if (PathService::Get(base_path_key_, &base_path_)) {
+    FilePath json_file;
+    json_file =
+        base_path_.Append(FILE_PATH_LITERAL("external_extensions.json"));
 
-  scoped_ptr<DictionaryValue> prefs;
-  if (file_util::PathExists(json_file)) {
-    JSONFileValueSerializer serializer(json_file);
-    prefs.reset(ExtractPrefs(&serializer));
-  } else {
-    prefs.reset(new DictionaryValue());
+    if (file_util::PathExists(json_file)) {
+      JSONFileValueSerializer serializer(json_file);
+      prefs.reset(ExtractPrefs(&serializer));
+    }
   }
 
+  if (!prefs.get())
+    prefs.reset(new DictionaryValue());
+
   prefs_.reset(prefs.release());
   BrowserThread::PostTask(
        BrowserThread::UI, FROM_HERE,