18064 [fuchsia] Log unregistered platform channels only once (cla: yes, waiting for tree to go green)

18065 [web] Add TargetPlatform tests (cla: yes)

18066 1.17.0-3.4.pre Engine Cherrypicks (cla: yes)

18067 Update Fuchsia ComponentContext constructor call to renamed, but equvalent, method (cla: yes)

18070 Add an API for resyncing output streams (cla: yes)

18072 Remove the ResourceCleaner from the Android embedding (cla: yes, waiting for tree to go green)

18076 Don’t depend on an implicit transaction when presenting drawables on the raster thread. (cla: yes)