Make DBUS an optional dependency so Chromium can be built without it....

chrome/browser/profiles/profile_impl.cc

Index: chrome/browser/profiles/profile_impl.cc
===================================================================
--- chrome/browser/profiles/profile_impl.cc	(revision 77292)
+++ chrome/browser/profiles/profile_impl.cc	(working copy)
@@ -119,7 +119,9 @@
 #if defined(USE_GNOME_KEYRING)
 #include "chrome/browser/password_manager/native_backend_gnome_x.h"
 #endif
+#if defined(USE_DBUS)
 #include "chrome/browser/password_manager/native_backend_kwallet_x.h"
+#endif
 #include "chrome/browser/password_manager/password_store_x.h"
 #endif
 
@@ -1011,6 +1013,7 @@
 
   scoped_ptr<PasswordStoreX::NativeBackend> backend;
   if (desktop_env == base::nix::DESKTOP_ENVIRONMENT_KDE4) {
+#if defined(USE_DBUS)
     // KDE3 didn't use DBus, which our KWallet store uses.
     VLOG(1) << "Trying KWallet for password storage.";
     backend.reset(new NativeBackendKWallet());
@@ -1018,6 +1021,7 @@
       VLOG(1) << "Using KWallet for password storage.";
     else
       backend.reset();
+#endif
   } else if (desktop_env == base::nix::DESKTOP_ENVIRONMENT_GNOME ||
              desktop_env == base::nix::DESKTOP_ENVIRONMENT_XFCE) {
 #if defined(USE_GNOME_KEYRING)