enable warnings as errors - for real

experimentation shows that '*' does not match
bugprone-narrowing-conversions while * does.

This is proof the single quotes were all erroneous.

Test: builds
Bug: 153035880
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: I51727deef594760cf6aeb404d54bb02a3d7c77cf