Allow the default browser check to return "unknown" and reflect that in the UI.

chrome/browser/shell_integration_win.cc

Index: chrome/browser/shell_integration_win.cc
===================================================================
--- chrome/browser/shell_integration_win.cc	(revision 25499)
+++ chrome/browser/shell_integration_win.cc	(working copy)
@@ -44,13 +44,13 @@
   return true;
 }
 
-bool ShellIntegration::IsDefaultBrowser() {
+ShellIntegration::DefaultBrowserState ShellIntegration::IsDefaultBrowser() {
   // First determine the app path. If we can't determine what that is, we have
   // bigger fish to fry...
   std::wstring app_path;
   if (!PathService::Get(base::FILE_EXE, &app_path)) {
     LOG(ERROR) << "Error getting app exe path";
-    return false;
+    return UNKNOWN_DEFAULT_BROWSER;
   }
   // When we check for default browser we don't necessarily want to count file
   // type handlers and icons as having changed the default browser status,
@@ -69,7 +69,7 @@
         NULL, CLSCTX_INPROC, __uuidof(IApplicationAssociationRegistration),
         (void**)&pAAR);
     if (!SUCCEEDED(hr))
-      return false;
+      return UNKNOWN_DEFAULT_BROWSER;
 
     BrowserDistribution* dist = BrowserDistribution::GetDistribution();
     std::wstring app_name = dist->GetApplicationName();
@@ -84,10 +84,14 @@
       BOOL result = TRUE;
       hr = pAAR->QueryAppIsDefault(kChromeProtocols[i].c_str(), AT_URLPROTOCOL,
           AL_EFFECTIVE, app_name.c_str(), &result);
-      if (!SUCCEEDED(hr) || (result == FALSE)) {
+      if (!SUCCEEDED(hr)) {
         pAAR->Release();
-        return false;
+        return UNKNOWN_DEFAULT_BROWSER;
       }
+      if (result == FALSE) {
+        pAAR->Release();
+        return NOT_DEFAULT_BROWSER;
+      }
     }
     pAAR->Release();
   } else {
@@ -105,7 +109,7 @@
       RegKey key(root_key, key_path.c_str(), KEY_READ);
       std::wstring value;
       if (!key.Valid() || !key.ReadValue(L"", &value))
-        return false;
+        return NOT_DEFAULT_BROWSER;  // Or UNKNOWN_DEFAULT_BROWSER?

[Evan Martin, 2009/09/04 22:46:15]

If this registry key is something we set when we *are* the default browser, then
I think it's safe to delete your comment.

[Mike Mammarella, 2009/09/04 22:56:27]

I looked through the RegKey source but it wasn't clear to me whether either of
these conditions indicates that we would be unable to later set the key. If
either does indicate that, then "unknown" is the correct response for that
condition.

[kuchhal, 2009/09/04 23:05:12]

These are keys like <root>\Software\Classes\http\shell\open\command which should
always exist on Windows since it comes with IE preloaded. No browser I know
actually deletes this key. So if we can't read the value most likely we won't be
able to set it either so just setting the status to Unknown should be fine.

On 2009/09/04 22:56:27, Mike Mammarella wrote:

       // Need to normalize path in case it's been munged.
       CommandLine command_line(L"");
       command_line.ParseFromString(value);
@@ -117,10 +121,10 @@
                        short_path.end(),
                        short_app_path.begin(),
                        CaseInsensitiveCompare<wchar_t>())))
-        return false;
+        return NOT_DEFAULT_BROWSER;
     }
   }
-  return true;
+  return IS_DEFAULT_BROWSER;
 }
 
 // There is no reliable way to say which browser is default on a machine (each