Remove unused function after https://codereview.chromium.org/1586843002

Found by clang:
..\..\win8\delegate_execute\command_execute_impl.cc(69,6) :  error: unused function 'LaunchChromeBrowserProcess' [-Werror,-Wunused-function]

R=thakis@chromium.org
TBR=ananta@chromium.org
BUG=558054,82385

Review URL: https://codereview.chromium.org/1604693002

Cr-Commit-Position: refs/heads/master@{#370074}
1 file changed