12318 Update canvaskit backend (cla: yes)

12319 Add “type” to getDisplayRefreshRate protocol (cla: yes)

12320 Fix continuous event polling in the GLFW event loop (cla: yes)

12322 Tests for #11283 (cla: yes)

12323 README for the felt tool (cla: yes, platform-web)

12324 Roll buildroot and remove toolchain prefix. (cla: yes)

12325 [fuchsia] add fuchsia.netstack.Netstack (affects: engine, cla: yes, customer: pink)

12327 Revert “Provide dart vm initalize isolate callback so that children i… (cla: yes)