Collect known environment names and use them in the dropdown

If there are no known environment names, we can skip showing the filter
as an option. E.g. if it's simply not an RSC environment.

packages/react-devtools-shared/src/backend/fiber/renderer.js

@@ -722,6 +722,11 @@ export function getInternalReactConstants(version: string): {
   };
 }
 
+// All environment names we've seen so far. This lets us create a list of filters to apply.
+// This should ideally include env of filtered Components too so that you can add those as
+// filters at the same time as removing some other filter.
+const knownEnvironmentNames: Set<string> = new Set();
+
 // Map of one or more Fibers in a pair to their unique id number.
 // We track both Fibers to support Fast Refresh,
 // which may forcefully replace one of the pair as part of hot reloading.
@@ -2527,6 +2532,12 @@ export function attach(
           // Scan up until the next Component to see if this component changed environment.
           const componentInfo: ReactComponentInfo = (debugEntry: any);
           const secondaryEnv = getSecondaryEnvironmentName(fiber._debugInfo, i);
+          if (componentInfo.env != null) {
+            knownEnvironmentNames.add(componentInfo.env);
+          }
+          if (secondaryEnv !== null) {
+            knownEnvironmentNames.add(secondaryEnv);
+          }
           if (shouldFilterVirtual(componentInfo, secondaryEnv)) {
             // Skip.
             continue;
@@ -2957,6 +2968,12 @@ export function attach(
             nextChild._debugInfo,
             i,
           );
+          if (componentInfo.env != null) {
+            knownEnvironmentNames.add(componentInfo.env);
+          }
+          if (secondaryEnv !== null) {
+            knownEnvironmentNames.add(secondaryEnv);
+          }
           if (shouldFilterVirtual(componentInfo, secondaryEnv)) {
             continue;
           }