Allow GCF installation on machine with old IE 7 installs.

BUG=105386
TEST=install on Vista RTM (IE 7.0.6000.16386).  if it fails, the fix doesn't work.
R=robertshield@chromium.org

Review URL: http://codereview.chromium.org/8702010

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@111605 0039d316-1c4b-4281-b951-d872f2087c98

chrome_frame/chrome_tab.cc

@@ -612,7 +612,9 @@ HRESULT RegisterElevationPolicy(bool reg, bool is_system) {
     // be able launch Chrome when running in low-integrity IE.
     hr = _AtlModule.UpdateRegistryFromResourceS(IDR_CHROMEFRAME_ELEVATION, reg);
     if (SUCCEEDED(hr)) {
-      hr = RefreshElevationPolicy();
+      // Ignore failures since old versions of IE 7 (e.g., 7.0.6000.16386, which
+      // shipped with Vista RTM) do not export IERefreshElevationPolicy.
+      RefreshElevationPolicy();
     }
   }
   return hr;