editor/build/build.py: Use 32-bit version of dartium/content_shell on macos/windows + bat script fixes
editor/build/build.py: Use 32-bit version of dartium/content_shell on macos/windows + bat script fixes

R=ricow@google.com

Review URL: https://codereview.chromium.org//59623003

git-svn-id: c93d8a2297af3b929165606efe145742a534bc71@29909 260f80e4-7a28-3924-810f-c04153c831b5

dartino/dart-sdk,dart-archive/dart-sdk,dartino/dart-sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-archive/dart-sdk,dart-archive/dart-sdk,dart-archive/dart-sdk,dart-archive/dart-sdk,dartino/dart-sdk,dart-archive/dart-sdk,dartino/dart-sdk,dartino/dart-sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-archive/dart-sdk,dart-archive/dart-sdk,dartino/dart-sdk,dartino/dart-sdk,dart-archive/dart-sdk,dart-lang/sdk,dartino/dart-sdk,dart-lang/sdk,dartino/dart-sdk