Do not create one GL context per CompositingIOSurface
Do not create one GL context per CompositingIOSurface, rather,
share a single GL context across all CompositingIOSurfaces that
are drawing to a given NSWindow (as determined by window number)
and have the same window ordering (above or below).
This cuts the regression in the ShutdownTests.TwentyTabs* from
81% to 47%. Most of the rest is from the cost of destroying the
renderers' GL contexts in the GPU process.
BUG=180463
Review URL: https://chromiumcodereview.appspot.com/13097002
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@192111 0039d316-1c4b-4281-b951-d872f2087c98
6 files changed
