fix text color of BlueButton on GTK-theme-mode Linux Aura.

chrome/browser/ui/libgtk2ui/native_theme_gtk2.cc

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/ui/libgtk2ui/native_theme_gtk2.h"
 
 #include <gtk/gtk.h>
 
 #include "chrome/browser/ui/libgtk2ui/chrome_gtk_menu_subclasses.h"
 #include "chrome/browser/ui/libgtk2ui/skia_utils_gtk2.h"
@@ skipping 218 matching lines @@
     case kColorId_ButtonEnabledColor:
       return GetButtonStyle()->text[GTK_STATE_NORMAL];
     case kColorId_ButtonDisabledColor:
       return GetButtonStyle()->text[GTK_STATE_INSENSITIVE];
     case kColorId_ButtonHighlightColor:
       return GetButtonStyle()->base[GTK_STATE_SELECTED];
     case kColorId_ButtonHoverColor:
       return GetButtonStyle()->text[GTK_STATE_PRELIGHT];
     case kColorId_ButtonHoverBackgroundColor:
       return GetButtonStyle()->bg[GTK_STATE_PRELIGHT];
+    // TODO(estade): determine a more distinct color for the Blue
+    // buttons.
+    case kColorId_BlueButtonEnabledColor:
+      return GetButtonStyle()->text[GTK_STATE_NORMAL];
+    case kColorId_BlueButtonDisabledColor:
+      return GetButtonStyle()->text[GTK_STATE_INSENSITIVE];
+    case kColorId_BlueButtonHighlightColor:
+      return GetButtonStyle()->base[GTK_STATE_SELECTED];
+    case kColorId_BlueButtonHoverColor:
+      return GetButtonStyle()->text[GTK_STATE_PRELIGHT];
 
     // Textfield
     case kColorId_TextfieldDefaultColor:
       return GetEntryStyle()->text[GTK_STATE_NORMAL];
     case kColorId_TextfieldDefaultBackground:
       return GetEntryStyle()->base[GTK_STATE_NORMAL];
     case kColorId_TextfieldReadOnlyColor:
       return GetEntryStyle()->text[GTK_STATE_INSENSITIVE];
     case kColorId_TextfieldReadOnlyBackground:
       return GetEntryStyle()->base[GTK_STATE_INSENSITIVE];
@@ skipping 155 matching lines @@
       fake_menu_.Own(gtk_custom_menu_new());
 
     fake_menu_item_ = gtk_custom_menu_item_new();
     gtk_menu_shell_append(GTK_MENU_SHELL(fake_menu_.get()), fake_menu_item_);
   }
 
   return gtk_rc_get_style(fake_menu_item_);
 }
 
 }  // namespace libgtk2ui