dillon1000/react

[pipeline] panicOnBailout -> panicThreshold; remove isDev logging

--- 

Changed `panicOnBailout: boolean` to `panicThreshold`, which has the following 
options. Note that `ALL_ERRORS` corresponds to `panicOnBailout = true` and 
`CRITICAL_ERRORS` corresponds to `panicOnBailout = false`. `NONE` is a new 
option. 

```js 

export type PanicThresholdOptions = 

// Bail out of compilation on all errors by throwing an exception. 

| "ALL_ERRORS" 

// Bail out of compilation only on critical or unrecognized errors. 

// Instead, silently skip the erroring function. 

| "CRITICAL_ERRORS" 

// Never bail out of compilation. Instead, silently skip the erroring 

// function or file. 

| "NONE"; 

``` 

Jest seems to run babel through a different pipeline than Metro and - 
(perhaps through its complex `require` interjection logic). When running jest 
tests, exceptions thrown by babel transforms will bubble up to the nearest 
exception boundary which is often the jest test itself. This may not be a useful 
signal to anyone running a jest test with Forget enabled, as the erroring code 
may be within Forget itself or a transitively required module. 

Another reason to immediately bailing out on critical errors is that we may want 
to record errors found in the rest of the file. 

--- 

I'm not convinced that this change makes sense. A counterargument is that any 
CriticalErrors *should* be reported as parse errors, regardless of the runtime 
mode. Anyhow, this would be useful long term for our static analysis scripts 
(e.g. collecting info on bailouts and compilation info e.g. # slots used for 
JSX) as we want to compile-as-much-as-possible in those.