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

ui/views/controls/button/label_button.cc

 // Copyright (c) 2012 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 "ui/views/controls/button/label_button.h"
 
 #include "base/logging.h"
 #include "grit/ui_resources.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/gfx/animation/throb_animation.h"
@@ skipping 347 matching lines @@
 void LabelButton::UpdateThemedBorder() {
   // Don't override borders set by others.
   if (!border_is_themed_border_)
     return;
 
   scoped_ptr<Border> label_button_border = CreateDefaultBorder();
 
 #if defined(OS_LINUX) && !defined(OS_CHROMEOS)
   views::LinuxUI* linux_ui = views::LinuxUI::instance();
   if (linux_ui) {
+    Border* default_border = label_button_border.get();
     SetBorder(linux_ui->CreateNativeBorder(this, label_button_border.Pass()));
+    label_->SetBackgroundColor(GetNativeTheme()->GetSystemColor(
+        ui::NativeTheme::kColorId_ButtonBackgroundColor));
+    // If we're using a system-themed border, make sure text is legible.
+    label_->SetAutoColorReadabilityEnabled(border() != default_border);

[Elliot Glaysher, 2014/05/23 21:07:01]

Do we want to be executing all this outside of BlueButton?

[Evan Stade, 2014/05/23 23:39:53]

I guess I get why you're asking -- because normal LabelButton doesn't need it.
But any time there's a non-default text color set, it is useful (BlueButton is
only one such instance). I don't think it should hurt to have this even for
normal LabelButtons. If there's a GTK theme where the fg and bg colors aren't
distinguishable from each other, that's broken.

But your question did make me investigate more and I found that hovering a
bluebutton with highcontrastinverse applied would leave the text white on a
white background. That's fixed by changing the background color of the label in
StateChanged().

   } else
 #endif
   {
     SetBorder(label_button_border.Pass());
   }
 
   border_is_themed_border_ = true;
 }
 
 void LabelButton::StateChanged() {
@@ skipping 49 matching lines @@
   return ui::NativeTheme::kNormal;
 }
 
 ui::NativeTheme::State LabelButton::GetForegroundThemeState(
     ui::NativeTheme::ExtraParams* params) const {
   GetExtraParams(params);
   return ui::NativeTheme::kHovered;
 }
 
 }  // namespace views