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..532bab2c8e56e4a63403bbfe3d4a50c97cf3270a 100644
--- a/chrome/common/chrome_switches.cc
+++ b/chrome/common/chrome_switches.cc
@@ -1138,7 +1138,11 @@ 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.
+// The same as the --class argument in X applications.  Overrides the WM_CLASS

[Lei Zhang, 2016/07/29 00:41:43]

Just -class, as seen in "man xterm"

[Tom (Use chromium acct), 2016/07/29 18:52:34]

-class in xterm is different.  xterm does not support --class

Try "gedit --class=Foo" and then "xprop WM_CLASS" and click on the gedit window
to test.

[Lei Zhang, 2016/07/29 19:03:39]

I thought more X apps supported -class, but it looks more like an xterm-ism.
OTOH, --class is probably a GTKism, since konqueror and other KDE apps don't
support it. It's fine to leave it as is. Users who need it will figure it out.

+// window property with the given 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