Give SxS distribution its own registration GUIDs.

chrome/installer/util/google_chrome_sxs_distribution.cc

Index: chrome/installer/util/google_chrome_sxs_distribution.cc
diff --git a/chrome/installer/util/google_chrome_sxs_distribution.cc b/chrome/installer/util/google_chrome_sxs_distribution.cc
index 1e623d995e45a689b1e0562fc96cdccab5614868..9967489471c47631dc59b47c5ad929a7955f13e7 100644
--- a/chrome/installer/util/google_chrome_sxs_distribution.cc
+++ b/chrome/installer/util/google_chrome_sxs_distribution.cc
@@ -16,7 +16,11 @@ namespace {
 const wchar_t kChromeSxSGuid[] = L"{4ea16ac7-fd5a-47c3-875b-dbf4a2008c20}";
 const wchar_t kChannelName[] = L"canary";
 const wchar_t kBrowserAppId[] = L"ChromeCanary";
+const wchar_t kBrowserProgIdPrefix[] = L"ChromeSSHTM";
+const wchar_t kBrowserProgIdDesc[] = L"Chrome Canary HTML Document";
 const int kSxSIconIndex = 4;
+const wchar_t kCommandExecuteImplUuidString[] =
+    L"{1BEAC3E3-B852-44F4-B468-8906C062422E}";
 
 // The Chrome App Launcher Canary icon is index 6; see chrome_exe.rc.
 const int kSxSAppLauncherIconIndex = 6;
@@ -24,7 +28,8 @@ const int kSxSAppLauncherIconIndex = 6;
 }  // namespace
 
 GoogleChromeSxSDistribution::GoogleChromeSxSDistribution()
-    : GoogleChromeDistribution() {
+    : GoogleChromeDistribution(),
+      enable_set_as_default_(false) {
   GoogleChromeDistribution::set_product_guid(kChromeSxSGuid);
 }
 
@@ -53,6 +58,14 @@ string16 GoogleChromeSxSDistribution::GetBaseAppId() {
   return kBrowserAppId;
 }
 
+string16 GoogleChromeSxSDistribution::GetBrowserProgIdPrefix() {
+  return kBrowserProgIdPrefix;
+}
+
+string16 GoogleChromeSxSDistribution::GetBrowserProgIdDesc() {
+  return kBrowserProgIdDesc;
+}
+
 string16 GoogleChromeSxSDistribution::GetInstallSubDir() {
   return GoogleChromeDistribution::GetInstallSubDir().append(
       installer::kSxSSuffix);
@@ -64,7 +77,11 @@ string16 GoogleChromeSxSDistribution::GetUninstallRegPath() {
 }
 
 bool GoogleChromeSxSDistribution::CanSetAsDefault() {
-  return false;
+  return enable_set_as_default_;

[gab, 2013/09/09 19:18:21]

I just talked about this with grt@; can we get the ok to make this return true,
always, but explicitly hide all the UI bits for SxS?

That way Canary will always register itself, it just won't be possible to make
it default through the UI (you'd have to go in Windows' Programs &
Features/Default Programs to give Chrome default -- which no one does by
accident).

This would avoid code-churn to enable this.

[grt (UTC plus 2), 2013/09/09 19:22:57]

If that's not an option, them I'm okay with gab's suggestion to have
BrowserDistribution::IsSetAsDefaultSupported() return CanSetAsDefault();

[gab, 2013/09/09 19:34:18]

ref:
https://codereview.chromium.org/23258005/diff/63029/chrome/installer/util/bro...

+}
+
+void GoogleChromeSxSDistribution::DebugEnableSetAsDefault() {
+  enable_set_as_default_ = true;
 }
 
 int GoogleChromeSxSDistribution::GetIconIndex(ShortcutType shortcut_type) {
@@ -80,9 +97,11 @@ bool GoogleChromeSxSDistribution::GetChromeChannel(string16* channel) {
   return true;
 }
 
-bool GoogleChromeSxSDistribution::GetCommandExecuteImplClsid(
+bool GoogleChromeSxSDistribution::GetCommandExecuteImplClsidString(
     string16* handler_class_uuid) {
-  return false;
+  if (handler_class_uuid)
+    *handler_class_uuid = kCommandExecuteImplUuidString;
+  return true;
 }
 
 bool GoogleChromeSxSDistribution::AppHostIsSupported() {