Issue #3377570 by catch, Wim Leers, mglaman, marcelovani, Kingdutch: Add PHP Fibers support to BigPipe

Issue #3007424 by acbramley, Spokje, mbovan, narendra.rajwar27, AaronBauman, ravi.shankar, aleevas, geek-merlin, jibran, YurkinPark, daffie, larowlan, Berdir, alexpott, marcelovani, catch, Lendude, mstrelan, tar_inet, Honza Pobořil, seanB, andrewbelcher, danflanagan8, susgo, sylus, sjpeters79, yogeshmpawar, raman.b: Multiple usages of FieldPluginBase::getEntity do not check for NULL, leading to WSOD

Revert "Issue #3007424 by acbramley, Spokje, mbovan, narendra.rajwar27, AaronBauman, ravi.shankar, aleevas, geek-merlin, jibran, YurkinPark, daffie, larowlan, alexpott, marcelovani, catch, Berdir, Lendude, mstrelan, tar_inet, andrewbelcher, seanB, Honza Pobořil, danflanagan8, susgo, yogeshmpawar, sylus, sjpeters79, raman.b: Multiple usages of FieldPluginBase::getEntity do not check for NULL, leading to WSOD"

This reverts commit 7ea52649.

Issue #3007424 by acbramley, Spokje, mbovan, narendra.rajwar27, AaronBauman, ravi.shankar, aleevas, geek-merlin, jibran, YurkinPark, daffie, larowlan, alexpott, marcelovani, catch, Berdir, Lendude, mstrelan, tar_inet, andrewbelcher, seanB, Honza Pobořil, danflanagan8, susgo, yogeshmpawar, sylus, sjpeters79, raman.b: Multiple usages of FieldPluginBase::getEntity do not check for NULL, leading to WSOD

Issue #1081266 by stefan.r, mikeytown2, jeroen.b, tsphethean, mfb, joseph.olstad, marcelovani: Avoid re-scanning module directory when a filename or a module is missing