GTK: Turn on the GTK+ integration by default.

This will regress default startup time for users by 50ms. This doesn't matter
because this is what the users want--I've lost count of the number bloggers,
people on twitter, and people in our IRC channel complaining about the lack of
GTK+ integration...when it's just not on by default.

BUG=none
TEST=none

Review URL: http://codereview.chromium.org/1442001

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@42804 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/chrome/browser/profile.cc b/chrome/browser/profile.cc
index 802ad29..b6a8716d 100644
--- a/chrome/browser/profile.cc
+++ b/chrome/browser/profile.cc
@@ -155,7 +155,8 @@
   prefs->RegisterBooleanPref(prefs::kEnableSpellCheck, true);
   prefs->RegisterBooleanPref(prefs::kEnableAutoSpellCorrect, true);
 #if defined(TOOLKIT_USES_GTK)
-  prefs->RegisterBooleanPref(prefs::kUsesSystemTheme, false);
+  prefs->RegisterBooleanPref(prefs::kUsesSystemTheme,
+                             GtkThemeProvider::DefaultUsesSystemTheme());
 #endif
   prefs->RegisterFilePathPref(prefs::kCurrentThemePackFilename, FilePath());
   prefs->RegisterStringPref(prefs::kCurrentThemeID,