Linux: Support the --class argument (Reland)

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 99ba806f65ec014b0f8bbefa0d169b80e9a9d9d7..2f58490932cd40e0cd9265eab9b3dbc34a6e2d75 100644
--- a/chrome/common/chrome_switches.cc
+++ b/chrome/common/chrome_switches.cc
@@ -1138,7 +1138,10 @@ const char kHelpShort[]                     = "h";
 // Specifies which password store to use (detect, default, gnome, kwallet).
 const char kPasswordStore[]                 = "password-store";
 
-// Updates X11Desktophandler::wm_user_time_ms with the latest X server time.
+// Sets WM_CLASS with this value.
+const char kWmClass[]                       = "class";
+
+// Updates X11DesktopHandler::wm_user_time_ms with the latest X server time.
 const char kWmUserTimeMs[]              = "wm-user-time-ms";
 #endif