Allow download Chrome page to set Chrome as default even if it is not a new install.

Read "make_default_for_user" preference from master_preferences file and set Chrome to default in installer if we are updating Chrome instead of installing a new version.
The problem here is that now that we set the default browser preference from a web page, we are using master_preferences to communicate this desire to the browser.
Because the user already has Chrome installed on his/her machine, the master_preferences file will not be written to their machine.
Instead, we check for this preference in the installer itself, and set Chrome to be default for the user here.

BUG=53656
TEST=Have Chrome installed on your machine, but *not* default browser.  Run setup.exe to install a new version of Chrome, with a master_preferences file that includes the distribution preference "make_default_for_user":true. (This reflects what happens when the user downloads Chrome with the "make default" option checked).
Chrome should be default browser.

Review URL: http://codereview.chromium.org/3342002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@58280 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 14 insertions, 1 deletions

diff --git a/chrome/installer/setup/install.cc b/chrome/installer/setup/install.cc
index f2d2e60..d11a51a 100644
--- a/chrome/installer/setup/install.cc
+++ b/chrome/installer/setup/install.cc
@@ -773,8 +773,21 @@ installer_util::InstallStatus installer::InstallOrUpdateChrome(
       installer_util::GetDistroBooleanPreference(prefs,
           installer_util::master_preferences::kMakeChromeDefault,
           &make_chrome_default);
+
+      // If this is not the user's first Chrome install, but they have chosen
+      // Chrome to become their default browser on the download page, we must
+      // force it here because the master_preferences file will not get copied
+      // into the build.
+      bool force_chrome_default_for_user = false;
+      if (result == installer_util::NEW_VERSION_UPDATED ||
+          result == installer_util::INSTALL_REPAIRED) {
+        installer_util::GetDistroBooleanPreference(prefs,
+            installer_util::master_preferences::kMakeChromeDefaultForUser,
+            &force_chrome_default_for_user);
+      }
+
       RegisterChromeOnMachine(install_path, system_install,
-                              make_chrome_default);
+          make_chrome_default || force_chrome_default_for_user);
     }
 
     std::wstring latest_version_to_keep(new_version.GetString());