28100 [UWP] Add all mouse buttons support (cla: yes, waiting for tree to go green, platform-windows, needs tests)

28124 Fix SkXfermode doc link in lib/ui/painting.dart (cla: yes, needs tests)

28128 Revert “Add bundletool to DEPS and remove outdated header comment” (cla: yes, needs tests)

28136 macOS: Do not swap surface if nothing was painted (cla: yes, waiting for tree to go green, platform-macos, needs tests)

28158 fix leak of DisplayList storage (cla: yes, waiting for tree to go green, needs tests)

28161 Correct the return value of the method RunInIsolateScope (cla: yes, waiting for tree to go green, needs tests)