Don't hold onto SkBitmap in mus_demo.

services/ui/demo/mus_demo.cc

 // Copyright 2016 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 "services/ui/demo/mus_demo.h"
 
 #include "base/memory/ptr_util.h"
 #include "base/time/time.h"
 #include "services/service_manager/public/cpp/connector.h"
 #include "services/service_manager/public/cpp/service_context.h"
 #include "services/ui/public/cpp/gpu/gpu.h"
+#include "third_party/skia/include/core/SkBitmap.h"
 #include "third_party/skia/include/core/SkCanvas.h"
 #include "third_party/skia/include/core/SkColor.h"
 #include "third_party/skia/include/core/SkImageInfo.h"
 #include "third_party/skia/include/core/SkPaint.h"
 #include "third_party/skia/include/core/SkRect.h"
 #include "ui/aura/client/default_capture_client.h"
 #include "ui/aura/env.h"
 #include "ui/aura/mus/mus_context_factory.h"
 #include "ui/aura/mus/property_converter.h"
 #include "ui/aura/mus/window_tree_client.h"
@@ skipping 195 matching lines @@
   base::TimeTicks now = base::TimeTicks::Now();
 
   VLOG(1) << (now - last_draw_frame_time_).InMilliseconds()
           << "ms since the last frame was drawn.";
   last_draw_frame_time_ = now;
 
   angle_ += 2.0;
   if (angle_ >= 360.0)
     angle_ = 0.0;
 
-  // Re-initialize the bitmap
-  bitmap_.reset();
-  const gfx::Rect bounds = bitmap_window_->bounds();
+  const gfx::Rect& bounds = bitmap_window_->bounds();
+
+  // Allocate a bitmap of correct size.
+  SkBitmap bitmap;
   SkImageInfo image_info = SkImageInfo::MakeN32(bounds.width(), bounds.height(),
                                                 kPremul_SkAlphaType);
-  bitmap_.allocPixels(image_info);
+  bitmap.allocPixels(image_info);
 
   // Draw the rotated square on background in bitmap.
-  SkCanvas canvas(bitmap_);
+  SkCanvas canvas(bitmap);
   canvas.clear(kBgColor);
   // TODO(kylechar): Add GL drawing instead of software rasterization in future.
   DrawSquare(bounds, angle_, &canvas);
   canvas.flush();
 
-  gfx::ImageSkiaRep image_skia_rep(bitmap_, 1);
+  gfx::ImageSkiaRep image_skia_rep(bitmap, 1);
   gfx::ImageSkia image_skia(image_skia_rep);
   gfx::Image image(image_skia);
 
   window_delegate_->SetImage(image);
   bitmap_window_->SchedulePaintInRect(bitmap_window_->bounds());
 }
 
 }  // namespace demo
 }  // namespace aura