[Lock Screen Media Controls] Tweak UI based on new mocks

This CL rearranges the different components of the CrOS lock screen
media controls based on the newest mocks. This involves resizing most
of the child views and their spacings. The artwork was also resized
and re-positioned. Additionally, the close button was moved from the
main view to the header row child view.

Artist and title data about the current session will eventually be
placed to the right of the artwork, but right now this space is empty.

See the bug for before and after pictures.

Bug: 991647
Change-Id: I7b97f31982ccf2912bd2564d5241bfd849d21d92
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1746554
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Reviewed-by: Becca Hughes <beccahughes@chromium.org>
Commit-Queue: Mia Bergeron <miaber@google.com>
Cr-Commit-Position: refs/heads/master@{#686253}
void LockScreenMediaControlsView::GetAccessibleNodeData(
    ui::AXNodeData* node_data) {
  node_data->role = ax::mojom::Role::kListItem;
  node_data->AddStringAttribute(
      ax::mojom::StringAttribute::kRoleDescription,
      l10n_util::GetStringUTF8(
          IDS_ASH_LOCK_SCREEN_MEDIA_CONTROLS_ACCESSIBLE_NAME));

  if (!accessible_name_.empty())
    node_data->SetName(accessible_name_);
}

void LockScreenMediaControlsView::GetAccessibleNodeData(
    ui::AXNodeData* node_data) {
  node_data->role = ax::mojom::Role::kListItem;
  node_data->AddStringAttribute(
      ax::mojom::StringAttribute::kRoleDescription,
      l10n_util::GetStringUTF8(
          IDS_ASH_LOCK_SCREEN_MEDIA_CONTROLS_ACCESSIBLE_NAME));

  if (!accessible_name_.empty())
    node_data->SetName(accessible_name_);
}
