Remove the docs for incremental linking on Windows.

Most if not all of this information is out of date, as incremental
linking is now handled more-or-less automatically by the build
and you probably shouldn't mess with the settings.

R=brucedawson@chromium.org
BUG=670518

Review-Url: https://codereview.chromium.org/2549443004
Cr-Commit-Position: refs/heads/master@{#436220}

docs/windows_incremental_linking.md

-# Windows incremental linking
-
-Include in your `GYP_DEFINES`: `incremental_chrome_dll=1`. This turns on the
-equivalent of Use Library Dependency Inputs for the large components in the
-build.
-
-And if you want faster builds, it would be best to include to
-`component=shared_library` too unless you need a fully static link for some
-reason.
-
-Note that `incremental_chrome_dll=1` will probably not work on Visual Studio
-2008 builds. It may not work on Visual Studio 2010 builds either (pamg couldn't
-get it to work as of Nov 2012, encountering numerous link errors). You may have
-to use [ninja](ninja_build.md), which has incremental linking on by default.