Added capability on Windows to get the physical dimensions of your attached monitors. Also added this information to about:gpu for testing.

BUG=547914
TEST=go to the about:gpu URL and check for "Diagonal Monitor Size". it should show the size of your monitors

Review URL: https://codereview.chromium.org/1563183008

Cr-Commit-Position: refs/heads/master@{#369635}
5 files changed