Desktop chrome tab capture-chooseDesktopMedia()

chrome/browser/media/desktop_media_list.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 "chrome/browser/media/desktop_media_list.h"
+
+#include "third_party/skia/include/core/SkCanvas.h"
+#include "third_party/skia/include/core/SkImage.h"
+
+gfx::ImageSkia CreateEnlargedFaviconImage(gfx::Size size, gfx::Image& favicon) {
+  if (size.width() < 30 || size.height() < 30)
+    return gfx::ImageSkia();
+
+  // Create a bitmap.
+  SkBitmap result;
+  result.allocN32Pixels(size.width(), size.height(), true);
+  SkCanvas canvas(result);
+
+  // Fill with white.
+  canvas.drawARGB(255, 255, 255, 255);
+
+  // Draw black border.
+  const int thickness = result.width() / 30;
+  SkPaint paint;
+  paint.setARGB(255, 0, 0, 0);
+  paint.setStyle(SkPaint::kStroke_Style);
+  paint.setStrokeWidth(thickness);
+  canvas.drawRectCoords(thickness,                    // left
+                        thickness,                    // top
+                        result.width() - thickness,   // right
+                        result.height() - thickness,  // bottom
+                        paint);
+
+  // Draw a scaled favicon image into the center of result image to take up to
+  // 3/4 of result image.
+  const double scale = fmin(3.0 / 4 * result.width() / favicon.Width(),
+                            3.0 / 4 * result.height() / favicon.Height());
+  SkRect dest_rect;
+  dest_rect.set(result.width() / 2 - favicon.Width() * scale / 2,     // left
+                result.height() / 2 - favicon.Height() * scale / 2,   // top
+                result.width() / 2 + favicon.Width() * scale / 2,     // right
+                result.height() / 2 + favicon.Height() * scale / 2);  // bottom
+  const scoped_ptr<SkImage> temp_image(
+      SkImage::NewFromBitmap(favicon.AsBitmap()));
+  canvas.drawImageRect(temp_image.get(), dest_rect, nullptr);
+
+  // Create a skia image.
+  return gfx::ImageSkia::CreateFrom1xBitmap(result);
+}
+
+WebContentsRegistry* WebContentsRegistry::GetInstance() {
+  return base::Singleton<WebContentsRegistry>::get();
+}
+
+int WebContentsRegistry::RegisterWebContents(
+    content::WebContents* web_contents) {
+  IDMap<content::WebContents>::const_iterator it(&registered_web_contents_);
+  for (; !it.IsAtEnd(); it.Advance()) {
+    if (it.GetCurrentValue() == web_contents)
+      return it.GetCurrentKey();
+  }
+
+  Observe(web_contents);
+  return registered_web_contents_.Add(web_contents);
+}
+
+content::WebContents* WebContentsRegistry::GetWebContentsById(int id) {
+  return registered_web_contents_.Lookup(id);
+}
+
+WebContentsRegistry::WebContentsRegistry(){};
+WebContentsRegistry::~WebContentsRegistry(){};
+
+void WebContentsRegistry::WebContentsDestroyed(
+    content::WebContents* web_contents) {
+  IDMap<content::WebContents>::iterator it(&registered_web_contents_);
+  for (; !it.IsAtEnd(); it.Advance()) {
+    if (it.GetCurrentValue() == web_contents) {
+      registered_web_contents_.Remove(it.GetCurrentKey());
+      return;
+    }
+  }
+  NOTREACHED();
+}