29934 [web] clean-up dom_renderer.dart (cla: yes, platform-web)

29962 Add a comment in Image.toByteData to limit more encoders (cla: yes, waiting for tree to go green, platform-web, needs tests)

29994 [web] DomRenderer becomes FlutterViewEmbedder (cla: yes, platform-web)

30003 Non painting platform views (cla: yes, Work in progress (WIP), platform-web)

30007 [web] consolidate JS interop code (cla: yes, platform-web)

30035 Roll web_installers simulators package (cla: yes, waiting for tree to go green, platform-web)

30038 Fix sceneElement analysis error (cla: yes, platform-web)