Update Chromium

Pulls in following changes:

458ee912 Fix mixing chromium gles2 types with qt defined ones
c4241cdf Do not export .gitignore and .gitattributes
afbf89d1 [Backport] Add a .gitattributes file to force
         LF line-endings in .pins files

Task-number: QTBUG-66953
Change-Id: Ibc685f3afd84b9d1abbd54d538724facba09aa31
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>