Rewrite DownloadsApiTest in C++.

chrome/browser/extensions/api/downloads/downloads_api.h

Index: chrome/browser/extensions/api/downloads/downloads_api.h
diff --git a/chrome/browser/extensions/api/downloads/downloads_api.h b/chrome/browser/extensions/api/downloads/downloads_api.h
index 1179f462976ea21109d1e9f52c4f854fd11224a1..c8a148eb4b8c497e2588142aaa59a5b785aea4e6 100644
--- a/chrome/browser/extensions/api/downloads/downloads_api.h
+++ b/chrome/browser/extensions/api/downloads/downloads_api.h
@@ -42,7 +42,7 @@ extern const char kInvalidOperationError[];
 extern const char kInvalidOrderByError[];
 extern const char kInvalidQueryLimit[];
 extern const char kInvalidStateError[];
-extern const char kInvalidUrlError[];
+extern const char kInvalidURLError[];
 extern const char kNotImplementedError[];
 
 }  // namespace download_extension_errors
@@ -350,7 +350,8 @@ class DownloadsGetFileIconFunction : public AsyncDownloadsFunction {
 class ExtensionDownloadsEventRouter : public content::DownloadManager::Observer,
                                       public content::DownloadItem::Observer {
  public:
-  explicit ExtensionDownloadsEventRouter(Profile* profile);
+  explicit ExtensionDownloadsEventRouter(
+      Profile* profile, content::DownloadManager* manager);
   virtual ~ExtensionDownloadsEventRouter();
 
   virtual void ModelChanged(content::DownloadManager* manager) OVERRIDE;
@@ -358,6 +359,12 @@ class ExtensionDownloadsEventRouter : public content::DownloadManager::Observer,
   virtual void OnDownloadUpdated(content::DownloadItem* download) OVERRIDE;
   virtual void OnDownloadOpened(content::DownloadItem* download) OVERRIDE;
 
+  // Used for testing.
+  struct DownloadsNotificationSource {
+    std::string event_name;
+    Profile* profile;
+  };
+
  private:
   struct OnChangedStat {
     OnChangedStat();
@@ -370,7 +377,6 @@ class ExtensionDownloadsEventRouter : public content::DownloadManager::Observer,
   typedef std::map<int, base::DictionaryValue*> ItemJsonMap;
   typedef std::map<int, OnChangedStat*> OnChangedStatMap;
 
-  void Init(content::DownloadManager* manager);
   void DispatchEvent(const char* event_name, base::Value* json_arg);
 
   Profile* profile_;