avoid warnings compiling nacl64.exe

Gets rid of these when building in component=shared_library

breakpad_win64.lib(breakpad_win64.breakpad_win.obj) : warning LNK4049: locally defined symbol ?kProcessType@switches@@3QBDB (char const * const switches::kProcessType) imported
nacl_common_win64.lib(nacl_common_win64.nacl_cmd_line.obj) : warning LNK4049: locally defined symbol ?kLoggingLevel@switches@@3QBDB (char const * const switches::kLoggingLevel) imported
nacl_common_win64.lib(nacl_common_win64.nacl_cmd_line.obj) : warning LNK4049: locally defined symbol ?kDisableLogging@switches@@3QBDB (char const * const switches::kDisableLogging) imported
nacl_common_win64.lib(nacl_common_win64.nacl_cmd_line.obj) : warning LNK4049: locally defined symbol ?kEnableLogging@switches@@3QBDB (char const * const switches::kEnableLogging) imported
nacl_common_win64.lib(nacl_common_win64.nacl_cmd_line.obj) : warning LNK4049: locally defined symbol ?kNoSandbox@switches@@3QBDB (char const * const switches::kNoSandbox) imported
breakpad_win64.lib(breakpad_win64.breakpad_win.obj) : warning LNK4049: locally defined symbol ?kProcessType@switches@@3QBDB (char const * const switches::kProcessType) imported
nacl_common_win64.lib(nacl_common_win64.nacl_cmd_line.obj) : warning LNK4049: locally defined symbol ?kLoggingLevel@switches@@3QBDB (char const * const switches::kLoggingLevel) imported
nacl_common_win64.lib(nacl_common_win64.nacl_cmd_line.obj) : warning LNK4049: locally defined symbol ?kDisableLogging@switches@@3QBDB (char const * const switches::kDisableLogging) imported
nacl_common_win64.lib(nacl_common_win64.nacl_cmd_line.obj) : warning LNK4049: locally defined symbol ?kEnableLogging@switches@@3QBDB (char const * const switches::kEnableLogging) imported
nacl_common_win64.lib(nacl_common_win64.nacl_cmd_line.obj) : warning LNK4049: locally defined symbol ?kNoSandbox@switches@@3QBDB (char const * const switches::kNoSandbox) imported

R=joi@chromium.org

Review URL: https://codereview.chromium.org/38743003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@231223 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 231223