In wasm os.StdErr is invalid

[ldemailly]

Not sure what we can do though without any log but... at least it shouldn't panic

panic: runtime error: invalid memory address or nil pointer dereference

console_logging.go:98 +0x4

[ldemailly]

full stack

[Log] panic: runtime error: invalid memory address or nil pointer dereference (wasm_exec.js, line 22)
[Log] [signal 0xb code=0x0 addr=0x0 pc=0x0] (wasm_exec.js, line 22)
[Log]  (wasm_exec.js, line 22)
[Log] goroutine 1 [running]: (wasm_exec.js, line 22)
[Log] fortio.org/log.ConsoleLogging() (wasm_exec.js, line 22)
[Log] 	fortio.org/[email protected]/console_logging.go:98 +0x4 (wasm_exec.js, line 22)
[Log] fortio.org/log.ColorMode(...) (wasm_exec.js, line 22)
[Log] 	fortio.org/[email protected]/console_logging.go:129 (wasm_exec.js, line 22)
[Log] fortio.org/log.SetColorMode() (wasm_exec.js, line 22)
[Log] 	fortio.org/[email protected]/console_logging.go:106 +0xb (wasm_exec.js, line 22)
[Log] fortio.org/log.init.0() (wasm_exec.js, line 22)
[Log] 	fortio.org/[email protected]/logger.go:191 +0x2b (wasm_exec.js, line 22)

because we assume we can check in init if it's a console - we need to revert to stdout when invalid
(or wasm should provide a valid stream?)