Linux: make the "change proxy settings" button able to start several proxy config utilities.

base/linux_util.h

Index: base/linux_util.h
===================================================================
--- base/linux_util.h	(revision 23785)
+++ base/linux_util.h	(working copy)
@@ -35,7 +35,10 @@
 enum DesktopEnvironment {
   DESKTOP_ENVIRONMENT_OTHER,
   DESKTOP_ENVIRONMENT_GNOME,
-  DESKTOP_ENVIRONMENT_KDE,
+  // KDE3 and KDE4 are sufficiently different that we count
+  // them as two different desktop environments here.
+  DESKTOP_ENVIRONMENT_KDE3,
+  DESKTOP_ENVIRONMENT_KDE4,
 };
 
 // Return an entry from the DesktopEnvironment enum with a best guess
@@ -44,6 +47,12 @@
 // proxy settings, password manager, etc.
 DesktopEnvironment GetDesktopEnvironment(EnvironmentVariableGetter* env);
 
+// Return a string representation of the given desktop environment.
+// May return NULL in the case of DESKTOP_ENVIRONMENT_OTHER.
+const char* GetDesktopEnvironmentName(DesktopEnvironment env);
+// Convenience wrapper that calls GetDesktopEnvironment() first.
+const char* GetDesktopEnvironmentName(EnvironmentVariableGetter* env);
+
 }  // namespace base
 
 #endif  // BASE_LINUX_UTIL_H__