3887 [in_app_purchase] update min Flutter version to 1.20.0 (cla: yes, waiting for tree to go green, p: in_app_purchase, platform-ios)

3897 [in_app_purchase] Expose the NSLocale object (cla: yes, p: in_app_purchase, platform-ios)

3898 [image_picker] Image picker fix camera device (cla: yes, waiting for tree to go green, p: image_picker, platform-ios)