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

chrome/common/chrome_switches.cc

Index: chrome/common/chrome_switches.cc
diff --git a/chrome/common/chrome_switches.cc b/chrome/common/chrome_switches.cc
index 838e7bb93c638ca2d0208688046c9959cd3e8fc6..6dcd1e7dd68fd61f5636b3f29562994e8e993a33 100644
--- a/chrome/common/chrome_switches.cc
+++ b/chrome/common/chrome_switches.cc
@@ -21,6 +21,11 @@ namespace switches {
 // all work out.
 // -----------------------------------------------------------------------------
 
+// If set, Chrome will activate any existing browsers for a specific profile.
+// Used for example by the fast-user switcher in the Windows JumpList.
+const char kActivateExistingProfileBrowser[] =
+    "activate-existing-profile-browser";
+
 // Allows third-party content included on a page to prompt for a HTTP basic
 // auth username/password pair.
 const char kAllowCrossOriginAuthPrompt[]    = "allow-cross-origin-auth-prompt";