Pass a ui::PaintContext from ui::Layer to layer delegates.

ui/keyboard/keyboard_controller.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 "ui/keyboard/keyboard_controller.h"
 
 #include <set>
 
 #include "base/bind.h"
 #include "base/command_line.h"
@@ skipping 91 matching lines @@
   int GetNonClientComponent(const gfx::Point& point) const override {
     return HTNOWHERE;
   }
   bool ShouldDescendIntoChildForEventHandling(
       aura::Window* child,
       const gfx::Point& location) override {
     return true;
   }
   bool CanFocus() override { return false; }
   void OnCaptureLost() override {}
-  void OnPaint(gfx::Canvas* canvas) override {}
+  void OnPaint(const ui::PaintContext& context) override {}
   void OnDeviceScaleFactorChanged(float device_scale_factor) override {}
   void OnWindowDestroying(aura::Window* window) override {}
   void OnWindowDestroyed(aura::Window* window) override { delete this; }
   void OnWindowTargetVisibilityChanged(bool visible) override {}
   bool HasHitTestMask() const override {
     return !proxy_ || proxy_->HasKeyboardWindow();
   }
   void GetHitTestMask(gfx::Path* mask) const override {
     if (proxy_ && !proxy_->HasKeyboardWindow())
       return;
@@ skipping 449 matching lines @@
   proxy_->HideKeyboardContainer(container_.get());
 }
 
 void KeyboardController::AddBoundsChangedObserver(aura::Window* window) {
   aura::Window* target_window = window ? window->GetToplevelWindow() : nullptr;
   if (target_window)
     window_bounds_observer_->AddObservedWindow(target_window);
 }
 
 }  // namespace keyboard