Fix ResourceLoadTiming Resolution Issue 4th step - remove unused macros from common.gypi

This is the 4th step to fix ResourceLoadTiming resolution issue, as chromium and blink part
has been already smoothly switched to double resolution timestamps in ResourceLoadTiming, provisional
macros can be removed now.

Contributed by pan.deng@intel.com

BUG=242452

Review URL: https://chromiumcodereview.appspot.com/15962018

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@203373 0039d316-1c4b-4281-b951-d872f2087c98
1 file changed