create iconmanager as singleton class and cleanup code (#1)

* create iconmanager as singleton class and cleanup code

chromium_src/chrome/browser/icon_loader_win.cc

@@ -0,0 +1,75 @@
+// 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/icon_loader.h"
+
+#include <windows.h>
+#include <shellapi.h>
+
+#include "base/bind.h"
+#include "base/message_loop/message_loop.h"
+#include "base/threading/thread.h"
+#include "third_party/skia/include/core/SkBitmap.h"
+#include "ui/display/win/dpi.h"
+#include "ui/gfx/geometry/size.h"
+#include "ui/gfx/icon_util.h"
+#include "ui/gfx/image/image_skia.h"
+
+// static
+IconGroupID IconLoader::ReadGroupIDFromFilepath(
+    const base::FilePath& filepath) {
+  if (!IsIconMutableFromFilepath(filepath))
+    return filepath.Extension();
+  return filepath.value();
+}
+
+// static
+bool IconLoader::IsIconMutableFromFilepath(const base::FilePath& filepath) {
+  return filepath.MatchesExtension(L".exe") ||
+         filepath.MatchesExtension(L".dll") ||
+         filepath.MatchesExtension(L".ico");
+}
+
+// static
+content::BrowserThread::ID IconLoader::ReadIconThreadID() {
+  return content::BrowserThread::FILE;
+}
+
+void IconLoader::ReadIcon() {
+  int size = 0;
+  switch (icon_size_) {
+    case IconLoader::SMALL:
+      size = SHGFI_SMALLICON;
+      break;
+    case IconLoader::NORMAL:
+      size = 0;
+      break;
+    case IconLoader::LARGE:
+      size = SHGFI_LARGEICON;
+      break;
+    default:
+      NOTREACHED();
+  }
+
+  image_.reset();
+
+  SHFILEINFO file_info = {0};
+  if (SHGetFileInfo(group_.c_str(), FILE_ATTRIBUTE_NORMAL, &file_info,
+                    sizeof(SHFILEINFO),
+                    SHGFI_ICON | size | SHGFI_USEFILEATTRIBUTES)) {
+    std::unique_ptr<SkBitmap> bitmap(
+        IconUtil::CreateSkBitmapFromHICON(file_info.hIcon));
+    if (bitmap.get()) {
+      gfx::ImageSkia image_skia(
+          gfx::ImageSkiaRep(*bitmap, display::win::GetDPIScale()));
+      image_skia.MakeThreadSafe();
+      image_.reset(new gfx::Image(image_skia));
+      DestroyIcon(file_info.hIcon);
+    }
+  }
+
+  // Always notify the delegate, regardless of success.
+  target_task_runner_->PostTask(FROM_HERE,
+                                base::Bind(&IconLoader::NotifyDelegate, this));
+}