Add enable-app-launcher-shim to chrome://flags.

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 bde0dd1c28b98c4ac4f85a4e1c735e794f531a80..4463a462dc4c2918bd175fee059cd6af700664ac 100644
--- a/chrome/common/chrome_switches.cc
+++ b/chrome/common/chrome_switches.cc
@@ -1523,7 +1523,7 @@ const char kPasswordStore[]                 = "password-store";
 // optional argument: --enable-app-list-shim=0 will delete a previously created
 // .app folder for the app list shim. Any other argument, or no argument, will
 // create it.
-extern const char kEnableAppListShim[]      = "enable-app-list-shim";
+const char kEnableAppListShim[]             = "enable-app-list-shim";
 
 // Enables the tabs expose feature ( http://crbug.com/50307 ).
 const char kEnableExposeForTabs[]           = "enable-expose-for-tabs";