addressed PR comments

Author: XuechunHou

packages/firebase/index.d.ts

@@ -1773,7 +1773,7 @@ declare namespace firebase.remoteConfig {
    */
   export type LogLevel = 'debug' | 'error' | 'silent';
   /**
-   * An async function that returns true if current browser context supports initialization of remote config module
+   * Returns true if current browser context supports initialization of remote config module
    * (`firebase.remoteConfig()`).
    *
    * Returns false otherwise.

packages/remote-config/index.ts

@@ -77,7 +77,7 @@ export function registerRemoteConfig(
     }
     // Guards against the SDK being used when indexedDB is not available.
     if (!isIndexedDBAvailable()) {
-      throw ERROR_FACTORY.create(ErrorCode.INDEXED_DB_UNSUPPORTED);
+      throw ERROR_FACTORY.create(ErrorCode.INDEXED_DB_UNAVAILABLE);
     }
     // Normalizes optional inputs.
     const { projectId, apiKey, appId } = app.options;
@@ -159,8 +159,7 @@ async function isSupported(): Promise<boolean> {
   }
 
   try {
-    const isDBOpenable: boolean = await validateIndexedDBOpenable();
-    return isDBOpenable;
+    return await validateIndexedDBOpenable();
   } catch (error) {
     return false;
   }

packages/remote-config/src/errors.ts

@@ -31,7 +31,7 @@ export const enum ErrorCode {
   FETCH_THROTTLE = 'fetch-throttle',
   FETCH_PARSE = 'fetch-client-parse',
   FETCH_STATUS = 'fetch-status',
-  INDEXED_DB_UNSUPPORTED = 'indexed-db-unsupported'
+  INDEXED_DB_UNAVAILABLE = 'indexed-db-unavailable'
 }
 
 const ERROR_DESCRIPTION_MAP: { readonly [key in ErrorCode]: string } = {
@@ -66,7 +66,7 @@ const ERROR_DESCRIPTION_MAP: { readonly [key in ErrorCode]: string } = {
     ' Original error: {$originalErrorMessage}.',
   [ErrorCode.FETCH_STATUS]:
     'Fetch server returned an HTTP error status. HTTP status: {$httpStatus}.',
-  [ErrorCode.INDEXED_DB_UNSUPPORTED]:
+  [ErrorCode.INDEXED_DB_UNAVAILABLE]:
     'Indexed DB is not supported by current browser'
 };