Give SxS distribution its own registration GUIDs.

chrome/installer/util/browser_distribution.cc

Index: chrome/installer/util/browser_distribution.cc
diff --git a/chrome/installer/util/browser_distribution.cc b/chrome/installer/util/browser_distribution.cc
index 8a249272c802c84b96462548f3bf4ed1c7956b8a..4b1160dc3252c2578ae46b071d4fdcb8b7c7c5eb 100644
--- a/chrome/installer/util/browser_distribution.cc
+++ b/chrome/installer/util/browser_distribution.cc
@@ -36,9 +36,12 @@ namespace {
 const wchar_t kChromiumActiveSetupGuid[] =
     L"{7D2B3E1D-D096-4594-9D8F-A6667F12E0AC}";
 
-const wchar_t kCommandExecuteImplUuid[] =
+const wchar_t kCommandExecuteImplUuidString[] =
     L"{A2DF06F9-A21A-44A8-8A99-8B9C84F29160}";
 
+const GUID kCommandExecuteImplUuid = {0xA2DF06F9, 0xA21A, 0x44A8,
+    {0x8A, 0x99, 0x8B, 0x9C, 0x84, 0xF2, 0x91, 0x60}};
+
 // The Chromium App Launcher icon is index 1; see chrome_exe.rc.
 const int kAppLauncherIconIndex = 1;
 
@@ -199,6 +202,22 @@ string16 BrowserDistribution::GetBaseAppId() {
   return L"Chromium";
 }
 
+string16 BrowserDistribution::GetBrowserProgIdPrefix() {
+  // This used to be "ChromiumHTML", but was forced to become "ChromiumHTM"
+  // because of http://crbug.com/153349 as with the '.' and 26 characters
+  // suffix added on user-level installs, the generated progid for Chromium
+  // was 39 characters long which, according to MSDN (
+  // http://msdn.microsoft.com/library/aa911706.aspx), is the maximum length
+  // for a progid. It was however determined through experimentation that the
+  // 39character limit mentioned on MSDN includes the NULL character...

[gab, 2013/09/06 18:40:08]

The generic part of this comment should go in the header; the parts specific to
the fact that this had to change for Chromium can stay here.

[zturner, 2013/09/06 20:53:16]

Done.

[zturner, 2013/09/06 20:53:16]

Done.

+  return L"ChromiumHTM";
+}
+
+string16 BrowserDistribution::GetBrowserProgIdDesc() {
+  return L"Chromium HTML Document";
+}
+
+
 string16 BrowserDistribution::GetInstallSubDir() {
   return L"Chromium";
 }
@@ -253,10 +272,17 @@ string16 BrowserDistribution::GetVersionKey() {
   return L"Software\\Chromium";
 }
 
+bool BrowserDistribution::IsSetAsDefaultSupported() {
+  return true;

[gab, 2013/09/06 18:40:08]

How about having this return CanSetAsDefault() unless overriden to do something
else? Than all distributions for which this copies CanSetAsDefault don't need to
also override this method.

[zturner, 2013/09/06 20:53:16]

If we follow Greg's suggestion of deleting this method entirely and then using
the return value of GetBrowserProgIdPrefix() to check, then that would also
solve the problem.  I kind of agree that it's awkward to have to have another
virtual function for this purpose.

Another option is to keep this function, but make it a non-virtual base class
helper function that is implemented by calling the virtual
GetBrowserProgIdPrefix() function and checking if the return value is the empty
string.

That has the other issue you point out elsewhere though, where we rely on the
function returning an empty string instead of calling NOTREACHED(), so I guess
we have to decide how to deal with that.

One idea I had was to change the signature of CanSetAsDefault() to return a
tri-state enum {UNSUPPORTED, DISABLED, ENABLED}, but this would require a lot of
minor code tweaks to get various other parts of the codebase to compile, and
bring in some unnecessary owners.

It's possible we can do something like that as a subsequent changelist if you
like the idea.

[gab, 2013/09/09 19:34:17]

Meh, I prefer having two virtual functions with a default impl for one of them
based on the other.

+}
+
 bool BrowserDistribution::CanSetAsDefault() {
   return true;
 }
 
+void BrowserDistribution::DebugEnableSetAsDefault() {
+}
+
 bool BrowserDistribution::CanCreateDesktopShortcuts() {
   return true;
 }
@@ -265,9 +291,16 @@ bool BrowserDistribution::GetChromeChannel(string16* channel) {
   return false;
 }
 
-bool BrowserDistribution::GetCommandExecuteImplClsid(
+bool BrowserDistribution::GetCommandExecuteImplClsidString(
     string16* handler_class_uuid) {
   if (handler_class_uuid)
+    *handler_class_uuid = kCommandExecuteImplUuidString;
+  return true;
+}
+
+bool BrowserDistribution::GetCommandExecuteImplClsid(
+    CLSID* handler_class_uuid) {
+  if (handler_class_uuid)
     *handler_class_uuid = kCommandExecuteImplUuid;
   return true;
 }