27506 Added support for Swahili (material_sw.arb) (a: internationalization, cla: yes, framework)

27509 Removed double the (cla: yes, d: api docs, f: material design, framework)

27510 [Material] Allow slider shapes to be easily resized (cla: yes, f: material design, framework)

27511 Update dartdoc to 0.28.1+1 and add parameters for source-code linking (cla: yes, team)

27513 Add scroll performance test for flutter_gallery (cla: yes, team)

27519 Update OutlineButton on-pressed fill color (cla: yes, f: material design, framework)

27528 Fixed Cupertino Switch Demo (cla: yes, f: cupertino, framework, waiting for tree to go green)