Rework error and closure tracing

src/core/lib/iomgr/closure.c

src/core/lib/iomgr/closure.h

src/core/lib/iomgr/combiner.c

src/core/lib/iomgr/error.c

src/core/lib/iomgr/error.h

src/core/lib/iomgr/exec_ctx.c

src/core/lib/iomgr/executor.c

src/core/lib/surface/init.c