Tell Ninja how chrome.bc is built.

The chrome.bc file is built as a side effect of building chrome. If we tell Ninja this, we can run 'ninja chrome.soaap' right off the bat.
Drop one hardcoded '/home/kg365' from build.ninja.

We still need to figure out what to do with soaap_include_dir, however.
Fix another hardcoded kg365 path.