[OS X] Implement 'activate-with-open-windows' event for app.

atom/browser/api/atom_api_app.cc

@@ -171,6 +171,10 @@ void App::OnActivateWithNoOpenWindows() {
   Emit("activate-with-no-open-windows");
 }
 
+void App::OnActivateWithOpenWindows() {
+  Emit("activate-with-open-windows");
+}
+
 void App::OnWillFinishLaunching() {
   Emit("will-finish-launching");
 }

atom/browser/api/atom_api_app.h

@@ -42,6 +42,7 @@ class App : public mate::EventEmitter,
   void OnOpenFile(bool* prevent_default, const std::string& file_path) override;
   void OnOpenURL(const std::string& url) override;
   void OnActivateWithNoOpenWindows() override;
+  void OnActivateWithOpenWindows() override;
   void OnWillFinishLaunching() override;
   void OnFinishLaunching() override;
   void OnSelectCertificate(

atom/browser/browser.cc

@@ -98,6 +98,10 @@ void Browser::ActivateWithNoOpenWindows() {
   FOR_EACH_OBSERVER(BrowserObserver, observers_, OnActivateWithNoOpenWindows());
 }
 
+void Browser::ActivateWithOpenWindows() {
+  FOR_EACH_OBSERVER(BrowserObserver, observers_, OnActivateWithOpenWindows());
+}
+
 void Browser::WillFinishLaunching() {
   FOR_EACH_OBSERVER(BrowserObserver, observers_, OnWillFinishLaunching());
 }

atom/browser/browser.h

@@ -111,6 +111,9 @@ class Browser : public WindowListObserver {
   // Tell the application that application is activated with no open windows.
   void ActivateWithNoOpenWindows();
 
+  // Tell the application that application is activated with open windows.
+  void ActivateWithOpenWindows();
+
   // Tell the application the loading has been done.
   void WillFinishLaunching();
   void DidFinishLaunching();

atom/browser/browser_observer.h

@@ -47,6 +47,10 @@ class BrowserObserver {
   // dock icon).
   virtual void OnActivateWithNoOpenWindows() {}
 
+  // The browser is activated with open windows (usually by clicking on the dock
+  // icon).
+  virtual void OnActivateWithOpenWindows() {}
+
   // The browser has finished loading.
   virtual void OnWillFinishLaunching() {}
   virtual void OnFinishLaunching() {}

atom/browser/mac/atom_application_delegate.mm

@@ -53,6 +53,7 @@
                     hasVisibleWindows:(BOOL)flag {
   atom::Browser* browser = atom::Browser::Get();
   if (flag) {
+    browser->ActivateWithOpenWindows();
     return YES;
   } else {
     browser->ActivateWithNoOpenWindows();