Revert "Revert "AOSP/UnifiedEmail - Bumped the targetSdkVersion to 28 (maximum version). Used JobIntentservice API calls to replace context.startService.""

This reverts commit 20e45d84f9dc906034fb535ac35fb2a2ba9dc995.

Reason for revert: Email app needs to target API level 28+ 
Bug: 138276176
Bug: 119499886

Change-Id: I17abf17744dcd59948b40b1137c06e8e429e5adc
4 files changed