Remove obsolete about:flags entries on Windows.

These entries can enable features that are probably broken on Windows, so they shouldn't be allowed there.

BUG=329592

Review URL: https://codereview.chromium.org/101043009

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@241761 0039d316-1c4b-4281-b951-d872f2087c98
Fix ShellIntegrationTest failing on Linux Official Builder.

On GOOGLE_CHROME_BUILD it needs to expect Icon=google-chrome, not
Icon=chromium-browser.

BUG=328822

Review URL: https://codereview.chromium.org/117893002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@241762 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 241762