16595 improve surface state assert error messages (cla: yes)

16599 Implement Path extractPath, tangent APIs (cla: yes)

16601 Fix drawRRect failure when shader is specified (cla: yes)

16604 Manual roll of Dart 0299903f3e…edd64e6d5c (cla: yes)

16613 Roll buildroot to d14f3c708fb132381f7053b4ee9e628be915ed96 (cla: yes)

16621 [shell tests] Integrate Vulkan with Shell Tests (cla: yes)

16624 update hash code logic on the web (cla: yes)