(cherry picked from commit 22ed5cb4)

(cherry picked from commit 029158cd)

(cherry picked from commit 21063d50)

(cherry picked from commit c515f3a0)

(cherry picked from commit d4cdba55)

(cherry picked from commit b3316271)

(cherry picked from commit 63e40d15)

(cherry picked from commit 95ec1882)

(cherry picked from commit edf73f54)

(cherry picked from commit 81f9d7aa)

(cherry picked from commit 07ce434b)

(cherry picked from commit 0c81a1d3)

(cherry picked from commit f569167a)

(cherry picked from commit e9102094)

(cherry picked from commit d42ba975)

(cherry picked from commit e166de21)

(cherry picked from commit 992a700b)

(cherry picked from commit e3b0919d)

(cherry picked from commit bee7a8f6)

(cherry picked from commit 267671dc)

Handle setPosition, then setTime if length is not available.

(cherry picked from commit 0d3b889a)

(cherry picked from commit 5a9aab57)

(cherry picked from commit cff7e478)

(cherry picked from commit 315209e9)

(cherry picked from commit da59ddbf)

The length can be negative during initialisation.

(cherry picked from commit a88f93d6)

(cherry picked from commit 1af07e5d)

(cherry picked from commit 48af3512)

(cherry picked from commit 2fe2fab6)

(cherry picked from commit df24c752)

(cherry picked from commit e2ef5878)

(cherry picked from commit 99953410)

(cherry picked from commit c52f13ac)