[VrShell] Centralize color handling and enable close button on fullscreen

chrome/browser/android/vr_shell/textures/ui_texture.cc

 // Copyright 2017 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/android/vr_shell/textures/ui_texture.h"
 
 #include <set>
 #include <string>
 #include <vector>
 
@@ skipping 47 matching lines @@
 
 void UiTexture::SetMode(ColorScheme::Mode mode) {
   if (mode_ == mode)
     return;
   mode_ = mode;
   OnSetMode();
 }
 
 void UiTexture::OnSetMode() {}
 
+const ColorScheme& UiTexture::color_scheme() const {
+  return ColorScheme::GetColorScheme(mode());
+}
+
 std::vector<std::unique_ptr<gfx::RenderText>> UiTexture::PrepareDrawStringRect(
     const base::string16& text,
     const gfx::FontList& font_list,
     SkColor color,
     gfx::Rect* bounds,
     UiTexture::TextAlignment text_alignment,
     UiTexture::WrappingBehavior wrapping_behavior) {
   DCHECK(bounds);
 
   std::vector<std::unique_ptr<gfx::RenderText>> lines;
@@ skipping 118 matching lines @@
     fonts.push_back(gfx::Font(name, size));
   *font_list = gfx::FontList(fonts);
   return true;
 }
 
 void UiTexture::SetForceFontFallbackFailureForTesting(bool force) {
   force_font_fallback_failure_for_testing_ = force;
 }
 
 }  // namespace vr_shell