[Win] Add a fast profile switcher to the Windows taskbar item.

chrome/browser/ui/startup/startup_browser_creator.cc

Index: chrome/browser/ui/startup/startup_browser_creator.cc
diff --git a/chrome/browser/ui/startup/startup_browser_creator.cc b/chrome/browser/ui/startup/startup_browser_creator.cc
index 381f26533567411023af064022ddddb521e9decb..d913efa7b3bf7a4a9647c62832433ee8923a36a8 100644
--- a/chrome/browser/ui/startup/startup_browser_creator.cc
+++ b/chrome/browser/ui/startup/startup_browser_creator.cc
@@ -746,6 +746,15 @@ void StartupBrowserCreator::ProcessCommandLineAlreadyRunning(
     return;
   }
 
+  if (command_line.HasSwitch(switches::kActivateExistingProfileBrowser)) {

[tapted, 2014/11/04 23:10:48]

nit: perhaps comment here, something like "If the profile is loaded, it might
also have an existing browser to activate when using the taskbar-activated
profile switcher. In this case, skip regular command line processing, since that
will open a new tab."

[noms (inactive), 2014/11/10 21:46:08]

Done.

+    Browser* browser = chrome::FindTabbedBrowser(
+        profile, false, chrome::HOST_DESKTOP_TYPE_NATIVE);
+    if (browser) {
+      browser->window()->Activate();
+      return;
+    }
+  }
+
   ProcessCmdLineImpl(command_line, cur_dir, false, profile, Profiles(), NULL,
                      NULL);
 }