Add crostini ContainerId::GetDefault

Bug: 846190
Change-Id: I07130721969f741891c1b8902cc22445c68032b0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2217936
Commit-Queue: Joel Hockey <joelhockey@chromium.org>
Auto-Submit: Joel Hockey <joelhockey@chromium.org>
Reviewed-by: Julian Watson <juwa@google.com>
Cr-Commit-Position: refs/heads/master@{#772989}

chrome/browser/chromeos/crostini/crostini_util.cc

@@ -319,6 +319,10 @@ std::ostream& operator<<(std::ostream& ostream,
                  << container_id.container_name << "\")";
 }
 
+ContainerId ContainerId::GetDefault() {
+  return ContainerId(kCrostiniDefaultVmName, kCrostiniDefaultContainerName);
+}
+
 bool IsUninstallable(Profile* profile, const std::string& app_id) {
   if (!CrostiniFeatures::Get()->IsEnabled(profile) ||
       app_id == GetTerminalId()) {

chrome/browser/chromeos/crostini/crostini_util.h

@@ -42,6 +42,8 @@ struct LinuxPackageInfo;
 struct ContainerId {
   ContainerId(std::string vm_name, std::string container_name) noexcept;
 
+  static ContainerId GetDefault();
+
   std::string vm_name;
   std::string container_name;
 };