Alternate NTP: Don't overlap dev tools with bookmark bar

When docked vertically the dev tools view overlaps the bookmark bar.

This was a bug I introduced in r178367 when I changed the bookmark bar to overlap web contents.

To fix this I've made the following changes:
  - implement constrainSplitPosition: to prevent the splitter from being dragged past the bookmark bar
  - move the dev tools view into a container view. The container view resizes the dev tools view to be below the bookmark bar

BUG=173205
TEST=Open dev tools and verified that it never went under the bookmark bar.


Review URL: https://chromiumcodereview.appspot.com/12208060

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@181301 0039d316-1c4b-4281-b951-d872f2087c98
6 files changed