Add row styling

Summary:
Added styling / coloring to the new logs plugin, to bring it closer to feature completeness. Made the colum headers slightly more compact

Also made the API more foolproof by introducing the `useAssertStableRef` hook, that will protect against accidentally passing in props that would invalidate rendering every time.

Reviewed By: passy

Differential Revision: D26635063

fbshipit-source-id: 60b2af8db3cc3c12d8d25d922cf1735aed91dd2c

desktop/flipper-plugin/src/state/datasource/DataSource.tsx

@@ -328,6 +328,16 @@ export class DataSource<
     this.rebuildOutput();
   }
 
+  /**
+   * Returns a fork of this dataSource, that shares the source data with this dataSource,
+   * but has it's own FSRW pipeline, to allow multiple views on the same data
+   */
+  fork(): DataSource<T> {
+    throw new Error(
+      'Not implemented. Please contact oncall if this feature is needed',
+    );
+  }
+
   emitDataEvent(event: DataEvent<T>) {
     this.dataUpdateQueue.push(event);
     // TODO: schedule