Add CombinedDesktopMediaList class

chrome/browser/media/combined_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/combined_desktop_media_list.h"
+
+CombinedDesktopMediaList::CombinedDesktopMediaList(
+    std::vector<scoped_ptr<DesktopMediaList>>& media_lists) {

[Sergey Ulanov, 2016/01/26 18:06:54]

reference parameters can only be const. In this case you want to pass ownership
of the lists, so this shouldn't be a reference.

[GeorgeZ, 2016/01/27 00:17:38]

The reference is to avoid the copy of media_lists which will lead to compile
error, since it tries to copy scoped_ptrs. Const will not work here, since
media_list will lose its scoped_ptrs.

Please provide further instruction for this case.

+  DCHECK(media_lists.size());
+  for (size_t i = 0; i < media_lists.size(); i++)
+    media_lists_.push_back(std::move(media_lists[i]));

[Sergey Ulanov, 2016/01/26 18:06:54]

Don't need the loop, just move the whole list:
 media_lists_ = std::move(media_lists)

[GeorgeZ, 2016/01/27 00:17:38]

Done.

+}
+
+CombinedDesktopMediaList::~CombinedDesktopMediaList() {}
+
+void CombinedDesktopMediaList::SetUpdatePeriod(base::TimeDelta period) {
+  for (size_t i = 0; i < media_lists_.size(); i++)
+    media_lists_[i]->SetUpdatePeriod(period);
+}
+
+void CombinedDesktopMediaList::SetThumbnailSize(
+    const gfx::Size& thumbnail_size) {
+  for (size_t i = 0; i < media_lists_.size(); i++)

[Sergey Ulanov, 2016/01/26 18:06:54]

Here and everywhere in this file use range-based for loop:
http://en.cppreference.com/w/cpp/language/range-for

[GeorgeZ, 2016/01/27 00:17:37]

Done.

+    media_lists_[i]->SetThumbnailSize(thumbnail_size);
+}
+
+void CombinedDesktopMediaList::SetViewDialogWindowId(
+    content::DesktopMediaID dialog_id) {
+  for (size_t i = 0; i < media_lists_.size(); i++)
+    media_lists_[i]->SetViewDialogWindowId(dialog_id);
+}
+
+void CombinedDesktopMediaList::StartUpdating(
+    DesktopMediaListObserver* observer) {
+  observer_ = observer;
+  for (size_t i = 0; i < media_lists_.size(); i++)
+    media_lists_[i]->StartUpdating(this);
+}
+
+int CombinedDesktopMediaList::GetSourceCount() const {
+  int count = 0;
+  for (size_t i = 0; i < media_lists_.size(); i++)
+    count += media_lists_[i]->GetSourceCount();
+
+  return count;
+}
+
+const DesktopMediaList::Source& CombinedDesktopMediaList::GetSource(
+    int index) const {
+  for (size_t i = 0; i < media_lists_.size(); i++) {
+    int count = media_lists_[i]->GetSourceCount();
+    if (index < count)
+      return media_lists_[i]->GetSource(index);
+
+    index -= count;
+  }
+
+  DCHECK(0) << "Index is invalid.";

[Sergey Ulanov, 2016/01/26 18:06:54]

NOTREACHED()

[GeorgeZ, 2016/01/27 00:17:38]

Done.

+  return media_lists_[0]->GetSource(0);
+}
+
+void CombinedDesktopMediaList::OnSourceAdded(DesktopMediaList* list,
+                                             int index) {
+  int count = 0;
+  for (size_t i = 0; i < media_lists_.size(); i++) {
+    if (media_lists_[i].get() == list) {
+      observer_->OnSourceAdded(this, count + index);
+      return;
+    }
+    count += media_lists_[i]->GetSourceCount();
+  }
+}

[Sergey Ulanov, 2016/01/26 18:06:54]

Add NOTREACHED(). Same for methods below.

[GeorgeZ, 2016/01/27 00:17:38]

Done.

+
+void CombinedDesktopMediaList::OnSourceRemoved(DesktopMediaList* list,
+                                               int index) {
+  int count = 0;
+  for (size_t i = 0; i < media_lists_.size(); i++) {
+    if (media_lists_[i].get() == list) {
+      observer_->OnSourceRemoved(this, count + index);
+      return;
+    }
+    count += media_lists_[i]->GetSourceCount();
+  }
+}
+
+void CombinedDesktopMediaList::OnSourceMoved(DesktopMediaList* list,
+                                             int old_index,
+                                             int new_index) {
+  int count = 0;
+  for (size_t i = 0; i < media_lists_.size(); i++) {
+    if (media_lists_[i].get() == list) {
+      observer_->OnSourceMoved(this, count + old_index, count + new_index);
+      return;
+    }
+    count += media_lists_[i]->GetSourceCount();
+  }
+}
+
+void CombinedDesktopMediaList::OnSourceNameChanged(DesktopMediaList* list,
+                                                   int index) {
+  int count = 0;
+  for (size_t i = 0; i < media_lists_.size(); i++) {
+    if (media_lists_[i].get() == list) {
+      observer_->OnSourceNameChanged(this, count + index);
+      return;
+    }
+    count += media_lists_[i]->GetSourceCount();
+  }
+}
+
+void CombinedDesktopMediaList::OnSourceThumbnailChanged(DesktopMediaList* list,
+                                                        int index) {
+  int count = 0;
+  for (size_t i = 0; i < media_lists_.size(); i++) {
+    if (media_lists_[i].get() == list) {
+      observer_->OnSourceThumbnailChanged(this, count + index);
+      return;
+    }
+    count += media_lists_[i]->GetSourceCount();
+  }
+}