Adds -Wno-deprecated-register compiler flag.

This flag is used on strict compilation to avoid warnings regarding the
register keyword being used. It is used in several system headers and the
upcomming Clang 3.4 warns about it.
Remove an unused const variable.

The issue was detected by the upcomming Clang 3.4.
Remove unused const variables.

The issue was detected by the upcomming Clang 3.4.
Remove an unused const variable.

The issue was detected by the upcomming Clang 3.4.
Remove unused const variables.

The issue was detected by the upcomming Clang 3.4.
Remove an unused const variable.

The issue was detected by the upcomming Clang 3.4.
Remove an unused const variable.

The issue was detected by the upcomming Clang 3.4.
Remove an unused const variable.

The issue was detected by the upcomming Clang 3.4.
Remove an unused const variable.

The issue was detected by the upcomming Clang 3.4.
Remove unused const variables.

The issue was detected by the upcomming Clang 3.4.
Remove an unused const variable.

The issue was detected by the upcomming Clang 3.4.
Remove unused const variables.

The issue was detected by the upcomming Clang 3.4.
Remove an unused const variable.

The issue was detected by the upcomming Clang 3.4.