31874 add stderr to log processor for desktop (cla: yes)

31876 Revert “fix edge swiping and dropping back at starting point” (cla: yes)

31886 Revert “Handle notification errors” (cla: yes)

PRs closed in this release of flutter/engine

From Thu Feb 21 20:22:00 2019 -0800 to Wed May 1 16:56:00 2019 -0700

7494 Add engine support for scrollwheel events (cla: yes)

7776 Support ContextWrapper when instantiating a FlutterView. (cla: yes)

7783 Refactor ios play input sound logic. (cla: yes)

7803 [re-land] Use all font managers to discover fonts for strut. (cla: yes)