Allow chrome to become the os default handler for arbitrary protocols on mac/win.

chrome/installer/setup/setup_main.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <windows.h>
 #include <msi.h>
 #include <shellapi.h>
 #include <shlobj.h>
 
 #include <string>
@@ skipping 814 matching lines @@
   } else if (cmd_line.HasSwitch(installer::switches::kShowEula)) {
     // Check if we need to show the EULA. If it is passed as a command line
     // then the dialog is shown and regardless of the outcome setup exits here.
     std::wstring inner_frame =
         cmd_line.GetSwitchValueNative(installer::switches::kShowEula);
     *exit_code = ShowEULADialog(inner_frame);
     if (installer::EULA_REJECTED != *exit_code)
       GoogleUpdateSettings::SetEULAConsent(*installer_state, true);
   } else if (cmd_line.HasSwitch(
       installer::switches::kRegisterChromeBrowser)) {
+    installer::InstallStatus status = installer::UNKNOWN_STATUS;
     const Product* chrome_install =
         installer_state->FindProduct(BrowserDistribution::CHROME_BROWSER);
     if (chrome_install) {
       // If --register-chrome-browser option is specified, register all
-      // Chrome protocol/file associations as well as register it as a valid
-      // browser for Start Menu->Internet shortcut. This option should only
-      // be used when setup.exe is launched with admin rights. We do not
-      // make any user specific changes in this option.
+      // Chrome protocol/file associations, as well as register it as a valid
+      // browser for Start Menu->Internet shortcut,and also as a valid handler
+      // for a set of URL protocols that Chrome may become the default handler
+      // for through website use of registerProtocolHandler.
+      // The --register-url-protocol performs the same actions as

[grt (UTC plus 2), 2011/05/25 14:35:45]

Please use good grammar in comments.  It's hard to tell what this is really
saying.  According to the code, --register-url-protocol requires
--register-chrome-browser, yet that isn't clear from the comment.  Also, the
code makes it look like this command:
--register-chrome-browser C:\blah\chrome.exe --register-url-protocol spam
is not a pure superset of this command:
--register-chrome-browser C:\blah\chrome.exe
(the latter calls RegisterChromeBrowser, the former calls
RegisterChromeForProtocol.)  Does registering a protocol also do all of the
normal associations?

[benwells, 2011/05/26 00:23:04]

Done.

+      // the --register-chrome-browser option, as well as also registering
+      // Chrome as a potential handler for the supplied protocol.
+      // These options should only be used when setup.exe is launched with admin
+      // rights. We do not make any user specific changes with this option.
       std::wstring chrome_exe(cmd_line.GetSwitchValueNative(
           installer::switches::kRegisterChromeBrowser));
       std::wstring suffix;
       if (cmd_line.HasSwitch(
           installer::switches::kRegisterChromeBrowserSuffix)) {
         suffix = cmd_line.GetSwitchValueNative(
             installer::switches::kRegisterChromeBrowserSuffix);
       }
-      *exit_code = ShellUtil::RegisterChromeBrowser(
-          chrome_install->distribution(), chrome_exe, suffix, false);
+      if (cmd_line.HasSwitch(
+          installer::switches::kRegisterURLProtocol)) {
+        std::wstring protocol = cmd_line.GetSwitchValueNative(
+            installer::switches::kRegisterURLProtocol);
+        if (ShellUtil::RegisterChromeForProtocol(chrome_install->distribution(),
+            chrome_exe, suffix, protocol, false))
+          status = installer::IN_USE_UPDATED;
+      } else {
+        if (ShellUtil::RegisterChromeBrowser(chrome_install->distribution(),
+            chrome_exe, suffix, false))
+          status = installer::IN_USE_UPDATED;
+      }
     } else {
       LOG(DFATAL) << "Can't register browser - Chrome distribution not found";
-      *exit_code = installer::UNKNOWN_STATUS;
     }
+    *exit_code = InstallUtil::GetInstallReturnCode(status);
   } else if (cmd_line.HasSwitch(installer::switches::kRenameChromeExe)) {
     // If --rename-chrome-exe is specified, we want to rename the executables
     // and exit.
     *exit_code = RenameChromeExecutables(original_state, installer_state);
   } else if (cmd_line.HasSwitch(
       installer::switches::kRemoveChromeRegistration)) {
     // This is almost reverse of --register-chrome-browser option above.
     // Here we delete Chrome browser registration. This option should only
     // be used when setup.exe is launched with admin rights. We do not
     // make any user specific changes in this option.
@@ skipping 341 matching lines @@
   if (!(installer_state.is_msi() && is_uninstall))
     // Note that we allow the status installer::UNINSTALL_REQUIRES_REBOOT
     // to pass through, since this is only returned on uninstall which is
     // never invoked directly by Google Update.
     return_code = InstallUtil::GetInstallReturnCode(install_status);
 
   VLOG(1) << "Installation complete, returning: " << return_code;
 
   return return_code;
 }