Merged r16018, r16026 into trunk branch.

Revert windows-specific part of r15937 for debug level 1.

Make optimized debug builds link against debug CRT.

R=machenbach@chromium.org
BUG=

Review URL: https://chromiumcodereview.appspot.com/22192002

git-svn-id: https://v8.googlecode.com/svn/trunk@16053 ce2b1a6d-e550-0410-aec6-3dcde31c8c00