25293 Implement computeLineMetrics (cla: yes)

25294 Roll Dart SDK from 5839c3386cca to 07c67e891edb (1 revision) (cla: yes, waiting for tree to go green)

25295 Roll Skia from 7b41798fd606 to 589adda93059 (1 revision) (cla: yes, waiting for tree to go green)

25296 Roll Fuchsia Mac SDK from jnG2ejqF6… to hi6Arsnrc… (cla: yes, waiting for tree to go green)

25297 Deduplicate plugin registration logic and make error logs visible (cla: yes, platform-android, waiting for tree to go green)

25299 Turn off insecure socket policy configuration in the engine (cla: yes, platform-android, platform-ios)