[video_player_platform_interface] add http headers (flutter#3702)

platform_interface portion of flutter#3671

Update LICENSE (flutter#3741)

[google_sign_in] Adds support to send `clientId` as a parameter (flut…

…ter#3640)

Add an AUTHORS file to each plugin (flutter#3725)

This ensures that the AUTHORS list is distributed with the plugins whose copyright blocks refer to the project authors, for ease of reference. This is currently a copy of the top-level authors list, but over time they are expected to diverge as people contribute to specific plugins.

This does not bump plugin versions or CHANGLELOGs, since it has no effect on the plugin itself; it will be picked up over time as we ship new versions of plugins.

Part of flutter/flutter#78448

[google_maps_flutter_platform_interface] Mark constructors as const f…

…or ids (flutter#3718)

[image_picker] Endorse image_picker_for_web (flutter#3717)

[ci] Add libgcrypt to Docker image. (flutter#3711)

As recommended in flutter/website#5466

[video_player] fixed misleading size and aspect ratio documentation (f…

…lutter#3668)

[image_picker] Implemented 2860 and added Unit Test to test functiona…

…lity (flutter#3685)

[image_picker] Implemented 2860 and added Unit Test to test functiona…

…lity (flutter#3685)