[MD] Don't use new OTR native-theming when using a custom browser theme.

chrome/browser/ui/views/dropdown_bar_host.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 "chrome/browser/ui/views/dropdown_bar_host.h"
 
 #include <algorithm>
 
 #include "chrome/browser/ui/view_ids.h"
 #include "chrome/browser/ui/views/dropdown_bar_host_delegate.h"
 #include "chrome/browser/ui/views/dropdown_bar_view.h"
 #include "chrome/browser/ui/views/frame/browser_view.h"
 #include "ui/events/keycodes/keyboard_codes.h"
 #include "ui/gfx/animation/slide_animation.h"
 #include "ui/gfx/scrollbar_size.h"
 #include "ui/views/focus/external_focus_tracker.h"
 #include "ui/views/focus/view_storage.h"
 #include "ui/views/widget/widget.h"
 
+namespace {
+
+// TODO(estade): move this to its own file and reuse for

[Evan Stade, 2016/01/27 00:44:18]

I would complete this TODO before landing, but only if this general approach
lgty

+// OmniboxPopupContentsView::popup_.
+class ThemeCopyingWidget : public views::Widget {
+ public:
+  explicit ThemeCopyingWidget(views::Widget* role_model)
+      : role_model_(role_model) {}
+  ~ThemeCopyingWidget() override {}
+
+  const ui::NativeTheme* GetNativeTheme() const override {
+    return role_model_->GetNativeTheme();
+  }
+
+ private:
+  // The widget we'll copy our theme from.
+  views::Widget* role_model_;
+
+  DISALLOW_COPY_AND_ASSIGN(ThemeCopyingWidget);
+};
+
+}  // namespace
+
 // static
 bool DropdownBarHost::disable_animations_during_testing_ = false;
 
 ////////////////////////////////////////////////////////////////////////////////
 // DropdownBarHost, public:
 
 DropdownBarHost::DropdownBarHost(BrowserView* browser_view)
     : browser_view_(browser_view),
       clip_view_(new views::View()),
       view_(NULL),
@@ skipping 11 matching lines @@
 void DropdownBarHost::Init(views::View* host_view,
                            views::View* view,
                            DropdownBarHostDelegate* delegate) {
   DCHECK(view);
   DCHECK(delegate);
 
   view_ = view;
   delegate_ = delegate;
 
   // Initialize the host.
-  host_.reset(new views::Widget);
+  host_.reset(new ThemeCopyingWidget(browser_view_->GetWidget()));
   views::Widget::InitParams params(views::Widget::InitParams::TYPE_CONTROL);
   params.ownership = views::Widget::InitParams::WIDGET_OWNS_NATIVE_WIDGET;
   params.parent = browser_view_->GetWidget()->GetNativeView();
   params.opacity = views::Widget::InitParams::TRANSLUCENT_WINDOW;
   host_->Init(params);
   host_->SetContentsView(clip_view_);
   clip_view_->AddChildView(view_);
 
   SetHostViewNative(host_view);
 
@@ skipping 166 matching lines @@
       escape, ui::AcceleratorManager::kNormalPriority, this);
   esc_accel_target_registered_ = true;
 }
 
 void DropdownBarHost::UnregisterAccelerators() {
   DCHECK(esc_accel_target_registered_);
   ui::Accelerator escape(ui::VKEY_ESCAPE, ui::EF_NONE);
   focus_manager_->UnregisterAccelerator(escape, this);
   esc_accel_target_registered_ = false;
 }