killed the concept of customizable column sets per device in device logs

Summary:
No device was using this feature, so doesn't look like there is a reason to keep it.

...if somebody was about to use this feature, let me know :). But probably, if we need this, a much more simple solution is to determine the visible columns with a simple switch on device type in the logs plugin, even though that is strictly speaking less scalable. But the current solution feels a bit over-engineered for something that is not really used.

Marked [interesting] as I might be missing some background concept which would make this relevant as well.

Reviewed By: jknoxville, nikoant

Differential Revision: D22763507

fbshipit-source-id: ecdbc779cbbfa3b0b72c80b459b12c1a25bf3fc4

desktop/plugins/logs/logUtils.tsx

@@ -20,16 +20,6 @@ export function getLineCount(str: string): number {
   return count;
 }
 
-export function keepKeys<A>(obj: A, keys: Array<string>): A {
-  const result: A = {} as A;
-  for (const key in obj) {
-    if (keys.includes(key)) {
-      result[key] = obj[key];
-    }
-  }
-  return result;
-}
-
 export function pad(chunk: any, len: number): string {
   let str = String(chunk);
   while (str.length < len) {